Calumet Genesis 250Ws Auto Sensing Studio Flash Unit with LED Modelling Lamp, and Built-in Genesis Wireless Receivers for Remote dio enabled operation and auto sensing capability Built-in Genesis wireless receivers for remote, radio enabled operation and auto sensing capability. Extremely fast recycling times of under 1 second, and flash duration of up to 1/8000sec. Adjustable power in 1/10 steps and stroboscopic & high speed flash modes. The AS250 features 250w/s max. output power with a guide number of GN50. The AS250 will also accept Genesis and Elinchrom accessories.