These quick disconnects feature 1/4" barbed fittings which can be used with either 3/16", 1/4" or 5/16" line. The quick disconnect functionality is activated by a shrouded thumb latch. The temperature range is -40F to 180F. They can handle a vacuum to 120 psi - so you need not worry about them leaking gas. The internal valve spring is 316 type stainless steel and the o-ring is food grade buna-n. For the female side, see our H550B.