The Quasar BQ Battery Mount utilizes (2) Sony type NPF batteries to power Quasar Rainbow LED Tubes. Built by Block Battery it is designed to work with Q25 (2ft), Q50 (4ft), Q100 (8ft). Estimated run time for a Q25 is 2 hours. NPF batteries are readily available and best of all ... inexpensive. Unlike other LED tubes with batteries built in and not replaceable, the Quasar Rainbows can be powered constantly with a simple battery change. Easy to use, simply snap Rainbow Tube into battery mount, plug power cable into tube and pop on (2) NPF type batteries and you are good to go. Includes 5/8" diameter baby pin for mounting in c-stand grip head.