PEX clamps are also commonly called PEX cinch clamps and are pre-formed Stainless steel bands with a distinctive ear. PEX clamps are used in combination with a PEX clamp tool (or PEX cinch tool) to compress the PEX tubing over the barbs of a PEX crimp style fitting. They come in sizes from 3/8 in. to 1 in. with clamp size corresponding both to the pipe and fitting size, for example, 1/2 in. clamps for 1/2 in. PEX tubing and fittings, 3/4 in. - for 3/4 in. pipe and fittings and so on. PEX flow PEX clamps are the best on the market and set the industry standard in quality, precision and reliability. They are manufactured to ASTM F2098/F877 standards, feature universal clamp tool compatibility and 360 step less and tamper-evident design.