The lytro jy680l is a professional flashgun compatible with the lytro illum camera with af assist beam and a guide number of 58 iso 100 meter it supports 18 135 mm auto zoom wireless light controlled trigger exposure compensation and rear curtain sync it supports pc sync socket 3 second quick recycle time and high speed continuous shooting at 8 flashes per second it has multiple wireless slave modes s1s2remote and can support an external power source