Compresses Stainless Steel Clamp Rings to secure PEX or PE-RT tubing to brass or poly crimp fittings. The 3-handle design version allows for one-handed gripping keeping the other hand free to hold a flashlight, ladder or pipe. One tool works with all size clamps from 3/8 in. to 1 in. When properly calibrated, this tool eliminates the need to check each fitting ring with a Go / No-Go gauge. Patented 3-handle design version allows for one-handed gripping and positioning of clamps. For use with SharkBite Stainless Steel Clamp Rings One tool clamps all sizes: 3/8 in. to 1 in. Meets ASTM F-2098 Standard