Use the CinchClamp tool for 3/8" to 1" (10mm to 28mm) PEX Cinch Clamps to make a safe and secure connection of PEX fittings. This tool combines 3 separate True Value tools for sizes 3/8 inches (true value #608-685 ), 1/2 inches (true value #608-933) and 3/4 inches (true value #608-826).