Specification: br br br - Physical Dimension: 36mmx18mmx74mm br br - Weight: Approx. 40g br br - Keyboard light source: Red laser diode br br - Keyboard language: English br br - Keyboard layout: 20.8mm sized QWERTY layout br br - Projection size: Approx. 241mm*101mm br br - Projected Keyboard location: Approx. 97.9mm from keyboard device br br - Keystroke Sound: Built in buzzer(Mute onoff the sound) br br - Visibility: Good contrast up to 1800 lux ambient illumination br br - Detection rate: Over 400 characters per minute br br - Detection algorithm: Multiple key stroke support br br - Effective key stroke: Approx. 2mm br br - Required projection surface: Non-reflective, opaque flat surface br br - Power source: The USB bus power br br - Lithium-ion battery power br br - The DC input power br br - Battery capacity: 700mAH(Max)3.7V Replaceable soft-pack type br br - Charger: Rating 800mA 5V br br - Interface: USB 1.1 and 2.0 for PC br br - Bluetooth(v2.0 class 2,class 3 )HID for Mobile devices br br - Switch mode: Switch the activeStandby mode manually br br - Power consumption: max. 2.4W4.2V br br - Use temperature: Approx. 0~50°C br br - Storage temperature: Approx.