diff --git a/index.d.ts b/index.d.ts
index a1707cf..7c3d6d5 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1,11 +1,11 @@
-import { Action, PreloadedState, Reducer, Store, StoreCreator, StoreEnhancer } from 'redux';
+import { Action, PreloadedState, Reducer, StoreCreator, StoreEnhancer } from 'redux';
 declare const REMEMBER_REHYDRATED = "@@REMEMBER_REHYDRATED";
 declare const REMEMBER_PERSISTED = "@@REMEMBER_PERSISTED";
 type SerializeFunction = (data: any) => any;
 type UnserializeFunction = (data: any) => any;
 type Driver = {
-    getItem: (key: String) => any;
-    setItem: (key: String, value: any) => any;
+    getItem: (key: string) => any;
+    setItem: (key: string, value: any) => any;
 };
 type Options = {
     prefix: string;
@@ -15,5 +15,5 @@ type Options = {
     persistWholeStore: boolean;
 };
 declare const rememberReducer: (reducers: Reducer) => Reducer;
-declare const rememberEnhancer: <S, A extends Action<any>, Ext>(driver: Driver, rememberedKeys: string[], { prefix, serialize, unserialize, persistThrottle, persistWholeStore }?: Partial<Options>) => (createStore: StoreCreator) => (rootReducer: Reducer<S, A>, initialState?: PreloadedState<S> | undefined, enhancer?: StoreEnhancer<Ext, {}> | undefined) => Store<S, A> & Ext;
+declare const rememberEnhancer: <S, A extends Action<any>, Ext>(driver: Driver, rememberedKeys: string[], { prefix, serialize, unserialize, persistThrottle, persistWholeStore }?: Partial<Options>) => (createStore: StoreCreator) => (rootReducer: Reducer<S, A>, initialState?: PreloadedState<S> | undefined, enhancer?: StoreEnhancer<Ext, {}> | undefined) => import("redux").Store<S, A> & Ext;
 export { rememberReducer, rememberEnhancer, REMEMBER_REHYDRATED, REMEMBER_PERSISTED };
diff --git a/package-lock.json b/package-lock.json
index da1403e..90b6f19 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
   "name": "redux-remember",
-  "version": "2.1.0",
+  "version": "2.1.1",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
diff --git a/package.json b/package.json
index 727823f..bd5fd29 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "redux-remember",
-  "version": "2.1.0",
+  "version": "2.1.1",
   "description": "Saves and loads your redux state from a key-value store of your choice",
   "main": "lib/index.js",
   "module": "es/index.js",
diff --git a/src/types.ts b/src/types.ts
index 36f9f64..73f8c98 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -2,8 +2,8 @@ export type SerializeFunction = (data: any) => any;
 export type UnserializeFunction = (data: any) => any;
 
 export type Driver = {
-  getItem: (key: String) => any;
-  setItem: (key: String, value: any) => any;
+  getItem: (key: string) => any;
+  setItem: (key: string, value: any) => any;
 };
 
 export type Options = {