For use with EOS cameras. A-TTL and TTL auto flash modes, manual flash at 8 output levels from full power to 1/128, flash exposure confirmation signal, automatic flash coverage from 24mm to 105mm lens coverage via internal motorized zoom with manual override, (built-in wide panel for coverage of 18mm lens), flash exposure compensation, flash head tilt and swivel for bounce flash, second curtain sync, stroboscopic effect with up to 100 consecutive bursts possible. AF auxiliary light which, when used with the EOS 1N, combines it's pattern with the camera's five focusing points. Batteries: 4-AA, NiCad OK. Optional external power sources: Compact Battery Pack E (6- AA or NiCad) and Transistor Pack E (can be used with either Battery Magazine TP which holds 6- C cells or Rechargeable NiCad pack TP).