The Dyna Lite Twinkle 400 Watt/Second Monolight is very lightweight, and perfect for location shooting as well as studio use.The variator dial clicks from full to 1/32 power, in 1/2 EV increments. The modeling light offers 3-way switching: full, half, and off. The built in optical slave may be switched off, as well as the audible flash confirmation beep.This monolight requires a Rapid Stand Adapter with a 3/8" threaded top, if it is being used on top of a light stand with a standard Baby Stud top.