This small device is the latest virtual laser projection keyboard compatible for smart phone and tablet that support bluetooth 3.0 above， Compatibile with Android， Windows， and iOS System.Colors: black， Silver and WhiteDimension: 38*18*75mmNet Weight:66gKeyboard light source: Red laser diodesKeyboard layout: 19mm sized QWERTY layout/ EnglishProjection keyboard size: 250mm(W)*110mm(H)Projection keyboard location: 100mm from the deviceRequired projection surface:Non-reflective， opaque flat surface Recognition rate: 350 characters per minuteKeystroke Sound Built in buzzer(Mute on/off the sound)Visibility: Good contrast up to 1800 lux ambient illuminationDetection algorithm: Multiple key stroke supportEffective key stroke: Approx. 2mmBattery : Li-Polymer， 1000mAH(Max) 3.7VBattery working time: 2 hoursBattery charging time: 3 hoursUSB interface USB 1.1 and 2.0. USB HID Ver. 1.0Bluetooth: V3.0(class 2)， HID Profile Ver. 1.0Frequency Range:2402-2480MHzChannel:79Modulation: GFSKAccessories 1 x manuel 1x usb cable