diff --git a/package.json b/package.json
index 7026bee..49eb927 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "pojazdownik",
-  "version": "1.7.3",
+  "version": "1.7.4",
   "private": true,
   "scripts": {
     "dev": "vite",
diff --git a/src/components/tabs/NumberGeneratorTab.vue b/src/components/tabs/NumberGeneratorTab.vue
index dad9f5c..f4a8b2a 100644
--- a/src/components/tabs/NumberGeneratorTab.vue
+++ b/src/components/tabs/NumberGeneratorTab.vue
@@ -1,77 +1,102 @@
 <template>
   <div class="number-generator tab">
     <div class="tab_header">
-      <h2>{{ $t("numgen.title") }}</h2>
+      <h2>{{ $t('numgen.title') }}</h2>
+      <h3>{{ $t('numgen.subtitle') }}</h3>
     </div>
 
     <div class="tab_content">
-      <div class="options">
-        <select v-model="chosenCategory" @change="randomizeTrainNumber()">
+      <div class="category-select">
+        <label for="category"> {{ $t('numgen.train-category') }}</label>
+        <select id="category" v-model="chosenCategory" @change="randomizeTrainNumber()">
           <option :value="null" disabled>
-            {{ $t("numgen.train-category") }}
+            {{ $t('numgen.train-category') }}
           </option>
-          <option
-            v-for="(_, category) in genData.categories"
-            :key="category"
-            :value="category"
-          >
+          <option v-for="(_, category) in genData.categoriesRules" :key="category" :value="category">
             {{ $t(`numgen.categories.${category}`) }}
           </option>
         </select>
+      </div>
 
-        <select v-model="beginRegionName" @change="randomizeTrainNumber()">
-          <option :value="null" disabled>
-            {{ $t("numgen.start-region") }}
-          </option>
-          <option
-            v-for="(_, name) in genData.regionNumbers"
-            :key="name"
-            :value="name"
-          >
-            {{ name }}
-          </option>
-        </select>
+      <div class="regions-select">
+        <div>
+          <label for="begin-region"> {{ $t('numgen.start-region') }}</label>
+          <select id="begin-region" v-model="beginRegionName" @change="randomizeTrainNumber()">
+            <option :value="null" disabled>
+              {{ $t('numgen.start-region') }}
+            </option>
+            <option v-for="(_, name) in genData.regionNumbers" :key="name" :value="name">
+              {{ name }}
+            </option>
+          </select>
+        </div>
 
-        <select v-model="endRegionName" @change="randomizeTrainNumber()">
-          <option :value="null" disabled>{{ $t("numgen.end-region") }}</option>
-          <option
-            v-for="(_, name) in genData.regionNumbers"
-            :key="name"
-            :value="name"
-          >
-            {{ name }}
-          </option>
-        </select>
+        <div>
+          <label for="end-region"> {{ $t('numgen.end-region') }}</label>
+          <select id="end-region" v-model="endRegionName" @change="randomizeTrainNumber()">
+            <option :value="null" disabled>{{ $t('numgen.end-region') }}</option>
+            <option v-for="(_, name) in genData.regionNumbers" :key="name" :value="name">
+              {{ name }}
+            </option>
+          </select>
+        </div>
       </div>
 
       <div class="generated-number" @click="copyNumber">
         <span v-if="trainNumber">
-          {{ $t("numgen.number-info") }}
+          {{ $t('numgen.number-info') }}
           <b class="text--accent">{{ trainNumber }}</b>
         </span>
-        <span v-else>{{ $t("numgen.warning") }}</span>
+        <span v-else>{{ $t('numgen.warning') }}</span>
       </div>
 
-      <!-- <div v-if="chosenCategory">
-        Current numbering rules: {{ $t(`numgen.rules.${chosenCategory}`) }};
+      <div class="category-rules" v-if="chosenCategory && categoryRules && trainNumber">
+        <!-- First & second digit (the same regions)  -->
+        <div v-if="beginRegionName && endRegionName && beginRegionName == endRegionName">
+          <b>Dwie pierwsze cyfry:</b> z puli
+          <b class="text--accent">{{ genData.sameRegions[beginRegionName].join(', ') }}</b>
+          dla obszaru {{ beginRegionName }}
+        </div>
 
-        <span v-if="beginRegionName && endRegionName">
-          <span v-if="beginRegionName == endRegionName">
-            pierwsze dwie cyfry:
-            {{ genData.sameRegions[beginRegionName].join(', ') }}
-            (numer w obrębie obszaru {{ beginRegionName }})
-          </span>
+        <!-- First & second digit (different regions)  -->
+        <div v-else>
+          <div>
+            <b>
+              Pierwsza cyfra: <span class="text--accent">{{ trainNumber[0] }}</span>
+            </b>
+            <span v-if="beginRegionName"> dla początkowego obszaru konstrukcyjnego {{ beginRegionName }}</span>
+            <span v-else>wybierz początkowy obszar konstrukcyjny</span>
+          </div>
 
-          <span v-else>
-            pierwsza cyfra: {{ genData.regionNumbers[beginRegionName] }}; druga cyfra:
-            {{ genData.regionNumbers[endRegionName] }}
-          </span>
-        </span>
-      </div> -->
+          <div>
+            <b>
+              Druga cyfra: <span class="text--accent">{{ trainNumber[1] }}</span>
+            </b>
+            <span v-if="endRegionName"> dla końcowego obszaru konstrukcyjnego {{ endRegionName }}</span>
+            <span v-else>wybierz początkowy obszar konstrukcyjny</span>
+          </div>
+        </div>
+
+        <!-- Third digit (non-passenger only) -->
+        <div v-if="categoryRules[0] != null">
+          <b>
+            Trzecia cyfra: <span class="text--accent">{{ categoryRules[0] }}</span>
+          </b>
+          dla kategorii {{ chosenCategory }}
+        </div>
+
+        <div>
+          <b> {{ categoryRules[1]?.length == 3 ? 'Trzy' : 'Dwie' }} ostatnie cyfry:</b>
+          z przedziału
+          <b class="text--accent">{{ categoryRules[1] }}-{{ categoryRules[2] }}</b>
+        </div>
+      </div>
+
+      <hr />
 
       <div class="tab_links">
         <a :href="$t('numgen.td2-wiki-link')" target="_blank">
-          {{ $t("numgen.td2-wiki") }}
+          {{ $t('numgen.td2-wiki') }}
         </a>
       </div>
 
@@ -79,10 +104,13 @@
 
       <div class="tab_actions">
         <button class="btn" @click="randomizeTrainNumber(true)">
-          {{ $t("numgen.action-random-region") }}
+          {{ $t('numgen.action-random-region') }}
         </button>
+
+        <button class="btn" @click="randomizeTrainNumber(true)">LOSUJ KATEGORIĘ</button>
+
         <button class="btn" @click="randomizeTrainNumber(false)">
-          {{ $t("numgen.action-random-number") }}
+          {{ $t('numgen.action-random-number') }}
         </button>
       </div>
     </div>
@@ -90,14 +118,15 @@
 </template>
 
 <script setup lang="ts">
-import { Ref, ref } from "vue";
-import { useI18n } from "vue-i18n";
+import { Ref, ref } from 'vue';
+import { useI18n } from 'vue-i18n';
 
-import genData from "../../constants/numberGeneratorData.json";
+import genData from '../../constants/numberGeneratorData.json';
+import { computed } from 'vue';
 
 const i18n = useI18n();
 type RegionName = keyof typeof genData.regionNumbers;
-type Category = keyof typeof genData.categories;
+type Category = keyof typeof genData.categoriesRules;
 
 const beginRegionName = ref(null) as Ref<RegionName | null>;
 const endRegionName = ref(null) as Ref<RegionName | null>;
@@ -108,31 +137,31 @@ const trainNumber = ref(null) as Ref<string | null>;
 const copyNumber = () => {
   if (trainNumber.value) {
     navigator.clipboard.writeText(trainNumber.value);
-    alert(i18n.t("numgen.alert"));
+    alert(i18n.t('numgen.alert'));
   }
 };
 
+const categoryRules = computed(() => {
+  if (!chosenCategory.value) return null;
+
+  return genData.categoriesRules[chosenCategory.value];
+});
+
 const randomizeTrainNumber = (randomizeRegions = false) => {
   // if (categoryRules.value == null) return;
 
   const regionKeys = Object.keys(genData.regionNumbers);
 
-  if (beginRegionName.value == null || randomizeRegions)
-    beginRegionName.value = regionKeys[
-      (regionKeys.length * Math.random()) << 0
-    ] as RegionName;
+  if (beginRegionName.value == null || randomizeRegions) beginRegionName.value = regionKeys[(regionKeys.length * Math.random()) << 0] as RegionName;
 
-  if (endRegionName.value == null || randomizeRegions)
-    endRegionName.value = regionKeys[
-      (regionKeys.length * Math.random()) << 0
-    ] as RegionName;
+  if (endRegionName.value == null || randomizeRegions) endRegionName.value = regionKeys[(regionKeys.length * Math.random()) << 0] as RegionName;
 
-  let number = "";
+  let number = '';
 
+  // Two first numbers (begin & end regions)
   if (beginRegionName.value == endRegionName.value) {
     const sameRegionsNumbers = genData.sameRegions[beginRegionName.value!];
-    const randRegionNumber =
-      sameRegionsNumbers[Math.floor(Math.random() * sameRegionsNumbers.length)];
+    const randRegionNumber = sameRegionsNumbers[Math.floor(Math.random() * sameRegionsNumbers.length)];
     number += randRegionNumber.toString();
   } else {
     const beginRegionNumber = genData.regionNumbers[beginRegionName.value!];
@@ -147,49 +176,63 @@ const randomizeTrainNumber = (randomizeRegions = false) => {
     return;
   }
 
-  if (chosenCategory.value == null) chosenCategory.value = "EI";
+  // Choose default category if it's not chosen
+  if (chosenCategory.value == null) chosenCategory.value = 'EI';
 
-  const rulesArray = genData.categories[chosenCategory.value]
-    .split(";")
-    .map((r) => ({
-      index: r.split(":")[0],
-      rule: r.split(":")[1],
-      nums: Number(r.split(":")[2] || "1"),
-    }));
+  // Get category rules
+  const [thirdNumber, minRange, maxRange] = categoryRules.value!;
 
-  rulesArray.forEach((r) => {
-    const range = r.rule.split("-");
+  // Third number
+  number += thirdNumber ?? '';
 
-    if (range.length == 1) number += r.rule;
-    else {
-      const [minRange, maxRange] = range;
-      const randRange = Math.floor(
-        Math.random() * (Number(maxRange) - Number(minRange)) +
-          Number(minRange),
-      ).toString();
+  // Remaining numbers
+  const rangeNums = minRange!.length;
+  const randRange = Math.floor(Math.random() * (Number(maxRange) - Number(minRange)) + Number(minRange)).toString();
+  const leadingZeros = new Array(Math.abs(randRange.length - rangeNums)).fill('0').join('');
 
-      number +=
-        new Array(Math.abs(randRange.length - r.nums)).fill("0").join("") +
-        randRange;
-    }
-  });
+  number += `${leadingZeros}${randRange}`;
 
   trainNumber.value = number;
 };
 </script>
 
 <style lang="scss" scoped>
-@import "../../styles/tab.scss";
-@import "../../styles/global.scss";
+@import '../../styles/tab.scss';
+@import '../../styles/global.scss';
 
-.options {
-  display: grid;
-  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
+label {
+  display: block;
+  font-weight: bold;
+  margin-bottom: 0.5em;
+}
+
+.category-select {
+  select {
+    width: auto;
+    min-width: 50%;
+  }
+
+  margin-bottom: 1em;
+}
+
+.regions-select {
+  display: flex;
+  align-items: center;
+  justify-content: center;
   gap: 0.5em;
 
+  div {
+    width: 100%;
+  }
+
   select {
     width: 100%;
   }
+
+  label {
+    display: block;
+    margin-bottom: 0.5em;
+  }
 }
 
 .generated-number {
@@ -204,14 +247,19 @@ const randomizeTrainNumber = (randomizeRegions = false) => {
   background-color: $secondaryColor;
 }
 
+.category-rules {
+  margin-bottom: 0.5em;
+}
+
 .tab_actions {
-  grid-template-columns: 1fr 1fr;
+  grid-template-columns: repeat(3, 1fr);
   margin: 0.5em 0;
 }
 
 .tab_links {
   display: flex;
   justify-content: flex-end;
+  margin: 0.25em 0;
 }
 
 @media screen and (max-width: $breakpointMd) {
@@ -221,8 +269,20 @@ const randomizeTrainNumber = (randomizeRegions = false) => {
 }
 
 @media screen and (max-width: $breakpointSm) {
-  .options select {
+  .regions-select {
+    flex-wrap: wrap;
+  }
+
+  .regions-select select {
     width: 100%;
   }
+
+  .category-select select {
+    min-width: 100%;
+  }
+
+  .category-rules {
+    text-align: center;
+  }
 }
 </style>
diff --git a/src/components/tabs/StockListTab.vue b/src/components/tabs/StockListTab.vue
index 651538c..55e532f 100644
--- a/src/components/tabs/StockListTab.vue
+++ b/src/components/tabs/StockListTab.vue
@@ -470,7 +470,7 @@ export default defineComponent({
 ul {
   position: relative;
   overflow: auto;
-  height: 550px;
+  max-height: 500px;
 }
 
 ul > li {
diff --git a/src/constants/numberGeneratorData.json b/src/constants/numberGeneratorData.json
index b5f9ab3..477acd5 100644
--- a/src/constants/numberGeneratorData.json
+++ b/src/constants/numberGeneratorData.json
@@ -1,37 +1,59 @@
 {
   "regionNumbers": {
-    "Warszawa": 1,
-    "Lublin": 2,
-    "Kraków": 3,
-    "Sosnowiec": 4,
-    "Gdańsk": 5,
-    "Wrocław": 6,
-    "Poznań": 7,
-    "Szczecin": 8,
-    "Rezerwa": 9
+    "Warszawa (1)": 1,
+    "Lublin (2)": 2,
+    "Kraków (3)": 3,
+    "Sosnowiec (4)": 4,
+    "Gdańsk (5)": 5,
+    "Wrocław (6)": 6,
+    "Poznań (7)": 7,
+    "Szczecin (8)": 8,
+    "Rezerwa (9)": 9
   },
   "sameRegions": {
     "Losowy": [
-      10, 11, 19, 91, 93, 97, 99, 20, 22, 29, 30, 33, 39, 40, 44, 49, 94, 50,
-      55, 59, 90, 95, 96, 66, 60, 69, 77, 70, 79, 88, 80, 89, 92, 98
+      10, 11, 19, 91, 93, 97, 99, 20, 22, 29, 30, 33, 39, 40, 44, 49, 94, 50, 55, 59, 90, 95, 96, 66, 60, 69, 77, 70, 79, 88, 80, 89, 92, 98
     ],
-    "Warszawa": [10, 11, 19, 91, 93, 97, 99],
-    "Lublin": [20, 22, 29],
-    "Kraków": [30, 33, 39],
-    "Sosnowiec": [40, 44, 49, 94],
-    "Gdańsk": [50, 55, 59, 90, 95, 96],
-    "Wrocław": [66, 60, 69],
-    "Poznań": [77, 70, 79],
-    "Szczecin": [88, 80],
-    "Rezerwa": [89, 92, 98]
+    "Warszawa (1)": [10, 11, 19, 91, 93, 97, 99],
+    "Lublin (2)": [20, 22, 29],
+    "Kraków (3)": [30, 33, 39],
+    "Sosnowiec (4)": [40, 44, 49, 94],
+    "Gdańsk (5)": [50, 55, 59, 90, 95, 96],
+    "Wrocław (6)": [66, 60, 69],
+    "Poznań (7)": [77, 70, 79],
+    "Szczecin (8)": [88, 80],
+    "Rezerwa (9)": [89, 92, 98]
   },
-  "categories": {
-    "EI": "2:00-99:2",
-    "MP/RP": "2:050-169:3",
-    "RO": "2:200-999:3",
-    "PW": "2:6;3:0-899:3",
-    "TM": "2:4;3:0-899:3",
-    "TK": "2:3;3:0-899:3",
-    "LT": "2:5;3:0-899:3"
+  "categoriesRules": {
+    "EI": [null, "00", "99"],
+    "EC": [null, "001", "049"],
+    "EN": [null, "001", "049"],
+
+    "RO": [null, "200", "999"],
+    "RP": [null, "050", "169"],
+    "RM": [null, "200", "999"],
+    "RA": [null, "200", "999"],
+
+    "MO": [null, "200", "999"],
+    "MP": [null, "050", "169"],
+    "MM": [null, "001", "049"],
+    "MH": [null, "170", "199"],
+
+    "PW": ["6", "000", "899"],
+    "PX": ["6", "000", "899"],
+
+    "TC": ["0", "000", "899"],
+    "TG": ["1", "000", "899"],
+    "TR": ["1", "000", "899"],
+    "TD": ["2", "000", "899"],
+    "TK": ["3", "000", "899"],
+    "TN": ["3", "000", "899"],
+    "TM": ["4", "000", "899"],
+    "TS": ["5", "000", "999"],
+
+    "LT": ["5", "000", "899"],
+    "LP": ["6", "000", "899"],
+
+    "ZN": ["9", "000", "899"]
   }
 }
diff --git a/src/locales/en.json b/src/locales/en.json
index 62bccc0..3b96d67 100644
--- a/src/locales/en.json
+++ b/src/locales/en.json
@@ -92,6 +92,7 @@
   },
   "numgen": {
     "title": "TRAIN NUMBER GENERATOR",
+    "subtitle": "Generates real train number based on Polish railway instruction Ir-11",
     "alert": "The number has been copied to your clipboard!",
     "start-region": "Beginning construction region",
     "end-region": "Terminating construction region",
@@ -103,22 +104,36 @@
     "action-random-region": "DRAW REGIONS",
     "action-random-number": "DRAW A NUMBER",
     "categories": {
-      "EI": "domestic express (EI)",
-      "MP/RP": "(inter)voivodeship bullet (MP/RP)",
-      "RO": "regional passenger (RO)",
-      "PW": "empty passenger (PW)",
-      "TM": "mass transport freight (TM)",
-      "TK": "non-mass transport freight (TK)",
-      "LT": "locomotive alone (LT)"
-    },
-    "rules": {
-      "EI": "4 digits - ends within the range of 00-99",
-      "MP/RP": "5 digits - ends within the range of 050-169",
-      "RO": "5 digits - ends within the range of 200-999",
-      "PW": "6 digits - '6' on the 3rd place; ends within the range of 000-899",
-      "TM": "6 digits - '4' on the 3rd place; ends within the range of 000-899",
-      "TK": "6 digits - '3' on the 3rd place; ends within the range of 000-899",
-      "LT": "6 digits - '5' on the 3rd place; ends within the range of 000-899"
+      "EI": "EI - domestic express",
+      "EC": "EC - international express",
+      "EN": "EN - domestic night express",
+
+      "MP": "MP - intervoivodeship bullet",
+      "RP": "RP - voivodeship bullet",
+      "MO": "MO - intervoivodeship regio",
+      "RO": "RO - voivodeship regio",
+
+      "MM": "MM - international bullet",
+      "MH": "MH - intervoivodeship bullet (night / )",
+      "RM": "RM - voivodeship osobowy international",
+      "RA": "RA - voivodeship osobowy algomeracyjny",
+
+      "PW": "PW - empty passenger",
+      "PX": "PX - empty test drive",
+
+      "TC": "TC - international freight (intermodal)",
+      "TG": "TG - international freight (cargo)",
+      "TR": "TR - international freight (no cargo)",
+      "TD": "TD - domestic freight (intermodal)",
+      "TM": "TM - domestic freight (cargo)",
+      "TN": "TN - domestic freight (no cargo)",
+      "TK": "TK - freight (stations & sidings service)",
+      "TS": "TS - empty freight test drive",
+
+      "LT": "LT - freight locomotive only",
+      "LP": "LP - passenger locomotive only",
+
+      "ZN": "ZN - inspection / diagnostic"
     }
   },
   "wiki": {
diff --git a/src/locales/pl.json b/src/locales/pl.json
index f2e8823..38083ea 100644
--- a/src/locales/pl.json
+++ b/src/locales/pl.json
@@ -92,6 +92,7 @@
   },
   "numgen": {
     "title": "GENERATOR NUMERU POCIĄGU",
+    "subtitle": "Generuje realny numer pociągu na podstawie instrukcji Ir-11",
     "alert": "Numer został skopiowany do twojego schowka!",
     "start-region": "Początkowy obszar konstrukcyjny",
     "end-region": "Końcowy obszar konstrukcyjny",
@@ -103,22 +104,36 @@
     "action-random-region": "LOSUJ OBSZARY",
     "action-random-number": "LOSUJ NUMER",
     "categories": {
-      "EI": "ekspres krajowy (EI)",
-      "MP/RP": "(między)wojewódzki pośpieszny (MP/RP)",
-      "RO": "wojewódzki osobowy (RO)",
-      "PW": "próżny \"służbowy\" (PW)",
-      "TM": "towarowy do przewozów masowych (TM)",
-      "TK": "towarowy do obsługi stacji (TK)",
-      "LT": "lokomotywa luzem (LT)"
-    },
-    "rules": {
-      "EI": "4 cyfry - końcówka z przedziału 00-99",
-      "MP/RP": "5 cyfr - końcówka z przedziału 050-169",
-      "RO": "5 cyfr - końcówka z przedziału 200-999",
-      "PW": "6 cyfr - '6' na 3. miejscu; końcówka z przedziału 000-899",
-      "TM": "6 cyfr - '4' na 3. miejscu; końcówka z przedziału 000-899",
-      "TK": "6 cyfr - '3' na 3. miejscu; końcówka z przedziału 000-899",
-      "LT": "6 cyfr - '5' na 3. miejscu; końcówka z przedziału 000-899"
+      "EI": "EI - ekspres krajowy",
+      "EC": "EC - ekspres międzynarodowy",
+      "EN": "EN - ekspres krajowy nocny",
+
+      "MP": "MP - międzywojewódzki pośpieszny",
+      "RP": "RP - wojewódzki pośpieszny",
+      "MO": "MO - międzywojewódzki osobowy",
+      "RO": "RO - wojewódzki osobowy",
+
+      "MM": "MM - międzynarodowy pośpieszny",
+      "MH": "MH - międzywoj. pośpieszny nocny / hotelowy",
+      "RM": "RM - wojewódzki osobowy międzynarodowy",
+      "RA": "RA - wojewódzki osobowy algomeracyjny",
+
+      "PW": "PW - próżny \"służbowy\"",
+      "PX": "PX - próżny próbny",
+
+      "TC": "TC - towarowy międzynarodowy intermodalny",
+      "TG": "TG - towarowy międzynarodowy masowy",
+      "TR": "TR - towarowy międzynarodowy niemasowy",
+      "TD": "TD - towarowy krajowy intermodalny",
+      "TM": "TM - towarowy krajowy masowy",
+      "TN": "TN - towarowy krajowy niemasowy",
+      "TK": "TK - towarowy do obsługi stacji i bocznic",
+      "TS": "TS - próżny próbny skład towarowy",
+
+      "LT": "LT - lokomotywa towarowa luzem",
+      "LP": "LP -lokomotywa pasażerska luzem",
+
+      "ZN": "ZN - inspekcyjny / diagnostyczny"
     }
   },
   "wiki": {
diff --git a/src/styles/tab.scss b/src/styles/tab.scss
index ddbec16..1716164 100644
--- a/src/styles/tab.scss
+++ b/src/styles/tab.scss
@@ -8,12 +8,18 @@
     padding: 0.5em 1em;
 
     background-color: $secondaryColor;
+    text-align: center;
 
     h2 {
       margin: 0;
       color: white;
       font-size: 1.35em;
-      text-align: center;
+    }
+
+    h3 {
+      margin: 0.5em 0 0 0;
+      font-size: 1.15em;
+      color: #aaa;
     }
 
     button {