This Elinchrom Skyport ECO Transmitter can be used as a spare transmitter for the EL Skyport Universal Receiver and Elinchrom flash units with a built-in EL Skyport Receiver, such as the D-lite-it 2 / 4, BXRi 250 / 500 and the Ranger Quadra AS.Once you use it the reason for its inclusion becomes obvious. The unit is tiny and lightweight, yet is able to trigger a flash at distances up to 262' with a battery that lasts for up to 30,000 flashes. Flash sync is a fast 1/200 sec. in Standard mode and a faster 1/250 sec. in Speed mode. The four channel unit has 40 Bit security encryption and compatibility with EL Skyport PC / Mac software 3.0.Speed Sync Feature, enables fast synchronization with SLR cameras up to 1/250 sec.Super lightweight and smallBattery life up to 30,000 flashesDistance range is approximately 164' (50 m) in Normal Sync and 98' (30 m) in Speed Sync mode4 frequency channels, no group settingsStatus LED flashes once or twice depending on if Normal-or Speed Sync mode is selectedThe LED indicates the battery status. At low LED brightness, exchange the battery