IR remote controller.

SPEC:
Max Key :57 key
Size: 175.5×49×23.2 (mm)
Battery :AAA battery *2

A convenient "whole house" feature lets you control every zone in your system from one location. You can change sources and raise or lower volume levels for all the keypads without leaving the room. For example, you could individually adjust the volume in every room for a party, briefly mute the volume on every keypad to tell your guests that dinner is ready, and then turn off all the volume controls in the house when the party ends.