Full flow check valve design. Threaded union allows pump to be removed without disrupting discharge piping. Saves time and money - Easy to install. Neoprene gasket and flapper, weighted with stainless steel backing plates and stainless steel rivet. Can be installed on vertical or horizontal pipe. Meets plumbing codes requiring a ball valve installed in conjunction with a check valve. All stainless steel screws. Replaceable flapper in the check valve. Extra wide hinge to reduce stress. Rated for 25 psi.