nRF24L01 is a single-chip radio transceiver for the worldwide 2.4 - 2.5 GHz ISM band. The transceiver consists of a fully integrated frequency synthesizer, a power amplifier, a crystal oscillator, a demodulator, modulator and Enhanced ShockBurst™ protocol engine. Output power, frequency channels, and protocol setup are easily programmable through an SPI interface. Current consumption is very low, only 9.0mA
at an output power of -6dBm and 12.3mA in RX mode. Built-in Power Down and Standby modes make power-saving easily realizable.
Ref: nRF24L01_prelim_prod_spec_1_2.pdf