This Two Stop Switching Flash Head has been a staple of Novatron professionals for decades.Use it for hair light accents or illuminate a background.Get creative about lighting anything at two stops less output.The 2120C,at full power can share an equal portion of the light,from the other heads plugged into the same pack,too,or it can be switched off.The modeling light adjusts, independently. 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<Off<-2stops 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"