diff --git a/hub.ts b/hub.ts
index e30106e..7355cab 100644
--- a/hub.ts
+++ b/hub.ts
@@ -20,8 +20,8 @@ export class Hub extends EventEmitter {
     public type: Consts.Hubs = Consts.Hubs.UNKNOWN;
     public uuid: string;
 
-    protected _ports: any = {};
-    protected _characteristics: any = {};
+    protected _ports: {[port: string]: Port} = {};
+    protected _characteristics: {[uuid: string]: Characteristic} = {};
 
     private _peripheral: Peripheral;
     private _rssi: number = -100;
diff --git a/lpf2.ts b/lpf2.ts
index 1f6c79a..a74893b 100644
--- a/lpf2.ts
+++ b/lpf2.ts
@@ -35,7 +35,7 @@ export class LPF2 extends EventEmitter {
     public autoSubscribe: boolean = true;
 
 
-    private _connectedDevices: any = {};
+    private _connectedDevices: {[uuid: string]: Hub} = {};
 
 
     constructor () {