BK04 - Sleek aluminum Wireless Keyboard - An elegant, ultrathin anodized aluminum enclosure - Build in Li-Polymer Battery - Easy on eyes. And hands. Description 1.sleek aluminum Wireless Keyboard 2.an elegant, ultrathin anodized aluminum enclosure 3.Build in Li-Polymer Battery 4.easy on eyes. And hands. 5.It's cable-free, so you're free to type wherever you like- with the keyboard in front of your computer or even on your lap. Just follow a few simple steps to pair them. Then you can move your keyboard anywhere within range and wirelessly type away Specification Bluetooth Standard: Bluetooth 3.0 Software Stack: HID V1.0 Chipset: AIROHA AB1100 /HT82K70E-L Battery: 2*AAA Button ON/OFF PAIRING, RF Specification: Frequency band 2.4G ISM band Frequency range: 2.402-2.480GHZ Spectrum: AFH Modulation: GFSK, 3.14/4 DQPSK, 8DPSK Antenna: PCB antenna Size: 24.5X10.5 cm.