Jelly Comb [Whisper-quiet] 2.4G Ultra Slim Portable Wireless Keyboard and Mouse Combo for Desktop, Windows 7/8/XP/Vista - Gold Reliable 2.4 GHz wireless connection: A tiny nano-receiver connects both the keyboard and mouse using just one USB port; Pencil-thin, sleek profile (0.23in thin) keyboard and 4.5 x 2.3 x 0.8 inches mouse combo; Low-profile, whisper-quiet keys ensure comfortable and smooth typing. Hot keys customized for Windows keep access to applications and media control in easy reach; DPI button easily adjusts the sensitivity of the mouse between 3 DPI levels (800/1000/1200) *NOTE: The Nano-receiver can be found in the battery compartment of the keyboard/mouse.* Requires 4 AAA batteries (2 for each unit) , batteries NOT included.