The XQC Series of quick connect tubing fittings from Value Plastics Inc., Fort Collins, Col., (valueplastic.com) fit ¼ and ⅜-in. tubing. The tubing can be made of PVC, polyurethane, and silicone, among other materiels. The 700 Series (shown) uses a single barb, which, the company says, provides more pull-off resistance than three-barb designs. The couplings also work with plastic and metal-button couplings. The devices handle pressures to 120 psi (8.28 bar) and can tolerate temperatures from -40 to 180F.