PEX Crimpers squeeze the copper rings used on PEX brass fittings. PEX Crimpers systems are used for potable water lines, radiant heat, snow melt and ice rink systems, among other applications. The design of these PEX crimpers eliminates tool marks and distortion on the rings. The tools crimp rings easily, making PEX installation a breeze. For one-hand use on 1/2 and 3/4 in PEX, consider the PEXOH12 or PEXOH34. Each Reed PEX Crimpers for copper rings comes with its own go/no-go gauge.