Featuring both a 2.4 GHz wireless radio transmitter and receiver, the Yongnuo YN320EX S Speedlite is a long range TTL, Manual and Multi flash unit capable of triggering other flashes from up to 328' away as well as being triggered with the RF-603 and RF-602 wireless transmitters and numerous other Yongnuo flash triggers and Sony optical slaves. The YN320EX S is powerful with a guide number of 102' at ISO 100 and 105mm. The unit is also quite versatile with a zoom range of 24-105mm. Additionally, this output can be adjusted from 1/1 to 1/128 power.