This Faithfull Standard Hydraulic Coupler is designed to suit most greasing applications. It is fitted with a spring-loaded ball check mechanism to prevent pressure loss and four fully hardened spring steel jaws for a long service life. The Faithfull Coupler is for use with hand operated grease guns, only with a working pressure of up to 3000psi -207bar. It fits Faithfull grease guns FAI GGHD and FAI GGMP and flexible hoses FAI GGHOSE12 and FAI GGHOSE18. Suitable for use with hand operated grease guns with a 1/8in BSPT thread and working pressure not exceeding 3000psi -207bar.