Watts TC Test Cock 1/4" M x 1/4" F (0006635)The Watts TC Test Cock is for use with backflow preventers, isolation valve for gauges, isolation valves for small equipment lines.Watts TC Test Cock Specifications: Full port ball valve design Screwdriver slot to open and close Available 1/8" M x 1/4" F (0006630) or 1/4" M x 1/4" F (0006635)