3/4in W X 1-1/2in H - 1/8ips Slip Telescopic Clutch with 1/4ips Female Thread - Unfinished Brass. Clutch Screws onto 1/4ips Thread and 1/8ips Pipe (3/8in OD) Pipe slips through the center. Tighten Clutch to hold slip rod in place.