The ProMaster SM180 Studio Monolight is a great choice for the aspiring studio photographer. The powerful 180 watt second head provides good light with variable power, modeling lamp, 4 channel wireless triggering and an optical slave all at an affordable price. Specifications: Power: 180 watt second (joule) at full power Color Temperature: 5600k ? 100k Guide Number: 151? /46m @ 100 ISO Modeling lamp: 75 watt / 120 volt G6.35 Bipin Halogen Lamp Power Setting: Continuous, 1/16th to full power Optical Slave: Built-in, effective up to 35? / 10m depending on conditions Recycling Time: .2 to 1.5 seconds Power Input: AC110 - 130 volt, 60Hz Fuse: 5 Amp ? 5A 250V Weight: 2 lb. 3 oz. approx. Size: 7 ?? L x 4 3/4? ? x 7 ?? H (aprox. With bracket collapsed) Accepts Bowens mount type accessories