Shanny SN-E3-RF is a transmitter and receiver for Shanny's own 2.4GHz radio flash system. It supports HSS (high-speed-sync) up to 1/8000s and 3 groups A, B, C and 15 channels. The transceiver can work as transmitter on camera and receiver on a flash. The big LCD makes it easy to use. It has a range of up to 200m. SN-E3-RF is specially comforable to use with Shanny SN600C-RF which has a compatible built-in radio receiver. Note that SN-E3-RF does not support Canons RT flash system, for this you would have to use Shanny SN-E3-RT radio transmitter.