The SP400A produces a superb warm light that will bathe your subjects in soft light. These are very high quality professional strobes that will give you years of service. They are perfect for commercial studios, location photographers as well as advanced amateurs. You can use this strobe for a main light, fill light, back light, or hair light. With the variable power setting you will have complete control over your light output. It is perfect for film or digital cameras. SPECIFICATIONS: Power Input: AC110-130 volt, 60 Hz. Flash Power: 400ws (joule) in full. Guide No. : 223ft/68m ISO100. Color Temperature: 5300K. Flash-tube Lifetime: over 10,000 typical flashing. Power Setting: 1/8 to full continuously. Recharge Time: 2 seconds in full. Flashing Duration: 1/600 sec. @t=0.1; 1/1000 sec. @t=0.5. Modeling Power: Halogen 100w. Sync Voltage: 6 volt. Fuse: 5A. Weight: 7 Lb (3.175kg).