Free Express Shipping! Sekonic RT-EL/PX Elinchrom & Phottix Transmitter Module For Speedmaster L-858D-U Light Meter, Adds Elinchrom EL-Skyport Radio System, Remote Control of Elinchrom Flashes, Adds Phottix Strato II/Ares II Protocols, Frequency: 2.4 GHz