Specifications TYPE : Clip on type serial controlled TTL auto zoom electric flash GUIDE NUMBER : 61 (ISO 100/m, 105mm head position) POWER SOURCE : Four AA type alka batteries or, Four AA type Ni-Cd batteries or, Four AA type Ni-MH Nickel Metal Hydride RECYCLING TIME : about 7.0 sec. (Alka batteries) about 5.0 sec. (Ni-Cd, Ni-MH Nickel Metal Hydride) NUMBER OF FLASHES : about 120 flashes (Alka batteries) about 160 flashes (Ni-Cd, Ni-MH Nickel Metal Hydride) FLASH DURATION : about 1/700sec (full power firing) FLASH ILLUMINATE ANGLE : 24mm-105mm motor powered control (17mm with Built-in Wide Panel) AUTO POWER OFF : Available