LED Blue backlight Key number. 33keys Supply Voltage:AAA size battery * 2pcs Key number. 33keysSupply Voltage:AAA size battery * 2pcsControl distance: Horizontal: α>=30° (A: 7meters). DC 3.0V Vertical: β>=20°(A: 7meters). DC 3.0V 10 meters in line of Min. DC 3.0VBlue LED working voltage:DC2.8V Min.Certification: PAHs Projector IR remote control with led blue backlight