With the introduction of the S1 500Ws HSS TTL Battery-Powered Monolight, Interfit joins the small group of manufacturers producing TTL monolights. The flash head is powered by an internal, removable 4500mAh lithium-ion battery that fits inside the head's housing. It has a 350 full-power flash capacity and can also run on AC while your battery is charging. It's controllable wirelessly at distances up to 328'.The S1 has 3 shooting modes: Wireless TTL for Canon, Nikon, or Sony; Manual Mode; and High-Speed Sync.

See recent price change history for the Interfit S1 500Ws HSS TTL Battery-Powered Monolight.