ZURN PEX™ QickClamp™ Crimp Rings. Stainless Steel (Type 304) mechanical fastener used to secure ZURN PEX™ tubing to Zurn® Qick/Sert® and QickSert CR® fittings. Integral locating flange and sight hole. The 1/2 QickClamp® stainless steel Crimp Ring utilizes a patented mechanical fastener that requires only one tool for 3/8, 1/2 and 3/4 in, speeding and easing installation. The gripping ribs assure ring stays in position after being pushed onto the tube for easy installation and proper alignment of ring, tubing, and fitting.