Universal fittings are designed to offer a quick connection on air hoses, typically for jackhammer and similar applications. To ensure that couplings are fully connected and to prevent accidental disconnection, safety clips should always be used. Universal couplings are rated to 110PSI under Mil. Spec. A-A-59553, however our two lug universals will handle 150PSI air or water. These fittings are not designed for steam service.