Ergoguys Wireless Mini Keyboard with Optical Trackball, Part # J81765
The Wireless Mini Keyboard FK-760 by is an RF keyboard with a built-in optical trackball. It operates at 2.4Ghz radio frequency, and has a 15 meter effective working range. It has a USB port and is the perfect wireless keyboard for any HTPC system.

System Requirements:
Mac and Windows 2000, XP, Vista and above compatible.

Specifications:
Frequency: 2.4GHz RF
Channel : 8 different frequencies with 65536 IDs per channel.
Standby Mode: after 8 minutes
Power: Uses 4-AA Batteries for up to 3 months use.
Trackball Resolution : Optical Type, 800 DPI
Trackball Size: 27 mm
Keyboard: 385 mm x 178 mm x 50 mm (15.1" x 7" x 1.9")
USB Receiver : 78mm x 21.5mm x 10mm (3" x 0.8" x 0.39")

OEM Part #: J81765