Manufactured to be used with Earl's new ultra-flex 650(TM) hose, Earl's QD hose ends are made to reduce time, space and weight issues in certain racing situations. These hose ends are thread less and the male and female designs are manufactured for smooth and effortless installations every time. They are coupled by a thread less clamshell closure, sold separately, that is manufactured by the leader in the industry - Adel Wiggins. Earl's QD hose ends are plated with the same mil-spec III class 1 hard anodizing and our exclusive Teflon(R) impregnation for a great reduction in the fluid flow friction. Our male ends also come with plasma coated nitrile O-rings installed for longer life. Teflon(R) is a registered trademark of DuPont Performance Elastomers.