This is the IR Transmitter and Receiver pair matched pair used in our IR proximity, White Line or Micromouse sensor. It consists of 5mm 940 nanometer wave length high power IR LED and photodiode having peak sensitivity at 940 nanometer wavelength. IR TX RX size: 5mm diameter package IR LED current rating: 30mA nominal, 600mA pulse loading at 1% duty cycle IR LED wavelength: 940nM Photodiode peak response wavelength: 940nM