Features : Electronic Construction : Automatic Insulated Gate Bipolar Transistor (IGBT) and series circuitry Flash Exposure Control : TTL automatic control with Nikon F5, F100, F80, F75, F65, FM3A, D2H, D1 series or D100; Non-TTL automatic control; Manual control: full, 1/2, 1/4, 1/8, 1/16, 1/32, 1/64 and 1/128 output Guide Number : 38 (with zoom head set at 35mm) Flash Coverage : 24mm to 105mm in 5mm zoom steps; 17mm, 14mm with built-in wide-flash adapter; 14mm with soft dome Film Speed Range in TTL auto flash mode : ISO 25 to 1600 Recycling Time : Approx. 2.9 seconds with supplied SD-800 Quick Recycling Battery Pack (Manual at full) Number of Flashes : Approx. 130 (Manual at full) AF-Assist Illuminator : Automatically fires LED beam toward subject when performing autofocus with Nikon AF SLRs in low-light conditions: cancelable Power Requirements : Four 1.5V LR6 (AA-size alkaline), 1.2V KR-AA (AA-size NiCd), 1.5V R6/AA-size Nickel, 1.2V (R6/AA-size Ni-MH) or 1.5V FR6/AA-size lithium batteries; DC Unit SD-7, High-Performance Battery Pack SD-8A, Power Bracket Unit SK-6A/6 Dimensions : Approx. 70.5 x 129.5 x 93.0mm Weight (without batteries) : Approx. 350g Other Features : Ready-light, open-flash button, sync/multiple flash terminal, modeling flash, LCD panel illumination Supplied Accessories (may differ by country or area) : Quick Recycling Battery Pack SD-800, Speedlight Stand AS-19, Speedlight Color Filter Set SJ-800, Diffusion Dome SW-10H, Soft Case SS-800