The Sea & Sea Optical YS Converter is an underwater photo accessory for TTL (automatic) strobe syncing. Optical converters allow you to leave sync cords behind and switch to fiber-optic cables. Fiber-optic cables are lighter, more durable and will not flood, unlike the standard sync cords.
The optical YS Converter allows you to switch from automatic (TTL) to manual during the dive via a push-button. It displays a light code that signifies which mode it is in (blue for TTL and green for manual). The converter runs on 2 x AAA batteries and will last 15 hours (alkaline) or 12 hours (NiMH). It also has an auto power off to conserve battery life.
This internal TTL converter connects to the camera's hot shoe and fits within the Sea & Sea MDX-D7100 and MDX-70D underwater housings for use with the Nikon D7100 DSLR and Canon 70D DSLR cameras.