Speedlight

The multi-functional Nikon SU-800 unit forms the nerve centre of any i-TTL multiple flash-lighting situation. Capable of metering and triggering groups of remote Speedlights in the Nikon Creative Lighting System

It only takes 3 seconds in charging after full power output. Even without new batteries, you can get the super charging speed that it only needs 4-5 seconds, you can completely get rid of the nightmare of anxious waiting for charging,. In addition, you can use the external power pack to accelerate the charging speed once more.