MR-8 is the dedicated receiver for the MC-8 transmitter. Signal format from the MR-8 is the same as general RC devices so it can be used with our RC car devices and also RTR models. Specifications:2.4GHz MX-F Multi ReceiverDimension: 27.0x28.0x15.0mmWeight: 7.0gOperation Voltage: 3.0~6.6vUseable power source: Dry Battery or Rechargeable battery, Ni-MH 3~5s Li-Fe 1~2s Li-Po 1sPlease notice voltage down when using Lithum batteryCurrent: less than 40mA (when receiving)Signal line: 3.3VNumber of channel: 8Frequency: 2.4GHzCompatible transmitter: MC-8Can not use with FHSS transmitter.