Membrane Keypad & Keyboard Specification Size: 5 x 5mm (minimum), 800 x 460mm (maximum) Thickness: 0. 15mm to 0. 3mm Color: blue, green, blue-green, white, and other colors Storage temperature: -40 to +80 degrees Celsius Operating temperature: -30 to +70 degrees Celsius Driving voltage: 50 to 150VAC Current: 0. 2mA/cm? Lifetime: 100, 000 hours