This extension is used with Northern Industrial drywall and panel hoist, Item# 143812, sold separately. Increases the lift from 11ft. to 15ft. for higher ceilings. For use with Item# 143812, sold separately Increases maximum lift to 15ft. (instead of standard 11ft.) Consists of: Two 6ft. telecoping sections that replace the standard 4ft. sections in the frame A longer cable is preinstalled in the telescoping sections, and must be attached to the winch drum