1 2 2 3 3 1 4 5 2 1 3 SPECIFICATION 6 (m) x 2 IMPORTANT - Canon E-TTL - P entax P-TTL - Sony ADI - Nikon i-TTL - Olympus TTL Auto This macro flash has TTL A UTO function b uilt-in. It is compatible with the f ollowing TTL metering system: In order to use this macro flash, you must also purchase a TUMAX DMF880 digital flash unit.