Our 2140-C 3-Way Switching Flash Head provides the control you need to ratio the output of the head. It can share an equal portion of the light, from the other heads plugged into the same pack, or reduce the light by one or two stops. The modeling light adjusts, independently, the same way. So you can stop-down the flash, but keep the modeling light at full power. The 1000 watt/second flash tube is color balanced to an excellent 5500 degrees Kelvin. The 100 watt Tungsram modeling lamp is very affordable. A 25' heavy duty cable is a terrific, manageable length for just about all needs. Flash Ratio/Modeling Switches Full<-1 stop,-2 stops Flash Tube 1000w/s-5500 degrees Kelvin Modeling Lamp 4101-100 watt Tungsram Cable Length 25 Feet Weight 1lb-11oz. Size(WxDxH) 6-1/2"x5"x6-1/2