diff --git a/src/field/pokemon-held-item-manager.ts b/src/field/pokemon-held-item-manager.ts
index dceaa7fae0c..839414f8790 100644
--- a/src/field/pokemon-held-item-manager.ts
+++ b/src/field/pokemon-held-item-manager.ts
@@ -10,6 +10,7 @@ import {
   type FormChangeItemSpecs,
   type HeldItemSaveData,
 } from "#app/items/held-item-data-types";
+import { getTypedEntries, getTypedKeys } from "#app/utils/common";
 
 export class PokemonItemManager {
   public heldItems: HeldItemDataMap;
@@ -34,58 +35,58 @@ export class PokemonItemManager {
 
   generateHeldItemConfiguration(restrictedIds?: HeldItemId[]): HeldItemConfiguration {
     const config: HeldItemConfiguration = [];
-    for (const [k, item] of Object.entries(this.heldItems)) {
-      const id = Number(k);
+    for (const [id, item] of getTypedEntries(this.heldItems)) {
       if (item && (!restrictedIds || id in restrictedIds)) {
         const specs: HeldItemSpecs = { ...item, id };
         config.push({ entry: specs, count: 1 });
       }
     }
-    for (const [k, item] of Object.entries(this.formChangeItems)) {
-      const id = Number(k);
-      const specs: FormChangeItemSpecs = { ...item, id };
-      config.push({ entry: specs, count: 1 });
+    for (const [id, item] of getTypedEntries(this.formChangeItems)) {
+      if (item) {
+        const specs: FormChangeItemSpecs = { ...item, id };
+        config.push({ entry: specs, count: 1 });
+      }
     }
     return config;
   }
 
   generateSaveData(): HeldItemSaveData {
     const saveData: HeldItemSaveData = [];
-    for (const [k, item] of Object.entries(this.heldItems)) {
-      const id = Number(k);
+    for (const [id, item] of getTypedEntries(this.heldItems)) {
       if (item) {
         const specs: HeldItemSpecs = { ...item, id };
         saveData.push(specs);
       }
     }
-    for (const [k, item] of Object.entries(this.formChangeItems)) {
-      const id = Number(k);
-      const specs: FormChangeItemSpecs = { ...item, id };
-      saveData.push(specs);
+    for (const [id, item] of getTypedEntries(this.formChangeItems)) {
+      if (item) {
+        const specs: FormChangeItemSpecs = { ...item, id };
+        saveData.push(specs);
+      }
     }
     return saveData;
   }
 
-  getHeldItems(): number[] {
-    return Object.keys(this.heldItems).map(k => Number(k));
+  getHeldItems(): HeldItemId[] {
+    return getTypedKeys(this.heldItems);
   }
 
-  getTransferableHeldItems(): number[] {
-    return Object.keys(this.heldItems)
+  getTransferableHeldItems(): HeldItemId[] {
+    return getTypedKeys(this.heldItems)
       .filter(k => allHeldItems[k].isTransferable)
-      .map(k => Number(k));
+      .map(k => k);
   }
 
-  getStealableHeldItems(): number[] {
-    return Object.keys(this.heldItems)
+  getStealableHeldItems(): HeldItemId[] {
+    return getTypedKeys(this.heldItems)
       .filter(k => allHeldItems[k].isStealable)
-      .map(k => Number(k));
+      .map(k => k);
   }
 
-  getSuppressableHeldItems(): number[] {
-    return Object.keys(this.heldItems)
+  getSuppressableHeldItems(): HeldItemId[] {
+    return getTypedKeys(this.heldItems)
       .filter(k => allHeldItems[k].isSuppressable)
-      .map(k => Number(k));
+      .map(k => k);
   }
 
   hasItem(itemType: HeldItemId): boolean {
@@ -93,7 +94,7 @@ export class PokemonItemManager {
   }
 
   hasItemCategory(categoryId: HeldItemCategoryId): boolean {
-    return Object.keys(this.heldItems).some(id => isItemInCategory(Number(id), categoryId));
+    return getTypedKeys(this.heldItems).some(id => isItemInCategory(id, categoryId));
   }
 
   getStack(itemType: HeldItemId): number {
@@ -117,7 +118,7 @@ export class PokemonItemManager {
   overrideItems(newItems: HeldItemDataMap) {
     this.heldItems = newItems;
     // The following is to allow randomly generated item configs to have stack 0
-    for (const [item, properties] of Object.entries(this.heldItems)) {
+    for (const [item, properties] of getTypedEntries(this.heldItems)) {
       if (!properties || properties.stack <= 0) {
         delete this.heldItems[item];
       }
@@ -208,7 +209,7 @@ export class PokemonItemManager {
   }
 
   getFormChangeItems(): FormChangeItem[] {
-    return Object.keys(this.formChangeItems).map(k => Number(k));
+    return getTypedKeys(this.formChangeItems).map(k => k);
   }
 
   getActiveFormChangeItems(): FormChangeItem[] {
diff --git a/src/items/trainer-item-manager.ts b/src/items/trainer-item-manager.ts
index 04da440cde6..f8329ac6341 100644
--- a/src/items/trainer-item-manager.ts
+++ b/src/items/trainer-item-manager.ts
@@ -7,6 +7,7 @@ import {
   type TrainerItemDataMap,
   type TrainerItemSpecs,
 } from "#app/items/trainer-item-data-types";
+import { getTypedEntries, getTypedKeys } from "#app/utils/common";
 
 export class TrainerItemManager {
   public trainerItems: TrainerItemDataMap;
@@ -29,8 +30,7 @@ export class TrainerItemManager {
 
   generateTrainerItemConfiguration(restrictedIds?: TrainerItemId[]): TrainerItemConfiguration {
     const config: TrainerItemConfiguration = [];
-    for (const [k, item] of Object.entries(this.trainerItems)) {
-      const id = Number(k);
+    for (const [id, item] of getTypedEntries(this.trainerItems)) {
       if (item && (!restrictedIds || id in restrictedIds)) {
         const specs: TrainerItemSpecs = { ...item, id };
         config.push({ entry: specs, count: 1 });
@@ -41,8 +41,7 @@ export class TrainerItemManager {
 
   generateSaveData(): TrainerItemSaveData {
     const saveData: TrainerItemSaveData = [];
-    for (const [k, item] of Object.entries(this.trainerItems)) {
-      const id = Number(k);
+    for (const [id, item] of getTypedEntries(this.trainerItems)) {
       if (item) {
         const specs: TrainerItemSpecs = { ...item, id };
         saveData.push(specs);
@@ -51,8 +50,8 @@ export class TrainerItemManager {
     return saveData;
   }
 
-  getTrainerItems(): number[] {
-    return Object.keys(this.trainerItems).map(k => Number(k));
+  getTrainerItems(): TrainerItemId[] {
+    return getTypedKeys(this.trainerItems);
   }
 
   hasItem(itemType: TrainerItemId): boolean {
diff --git a/src/utils/common.ts b/src/utils/common.ts
index 2e9f429f1c7..0bb4fada71c 100644
--- a/src/utils/common.ts
+++ b/src/utils/common.ts
@@ -285,6 +285,14 @@ export function getEnumValues(enumType: any): number[] {
     .map(v => Number.parseInt(v!.toString()));
 }
 
+export function getTypedKeys<T extends Record<number, any>, K extends number = Extract<keyof T, number>>(obj: T): K[] {
+  return Object.keys(obj).map(k => Number(k) as K);
+}
+
+export function getTypedEntries<T extends object>(obj: T): [keyof T, T[keyof T]][] {
+  return Object.entries(obj) as [keyof T, T[keyof T]][];
+}
+
 export function executeIf<T>(condition: boolean, promiseFunc: () => Promise<T>): Promise<T | null> {
   return condition ? promiseFunc() : new Promise<T | null>(resolve => resolve(null));
 }