Brass foot valves prevent water from back flowing into the water source. Boshart Industries Foot Valve, Lead-Free, Series: 17YBFVNL, 1-1/4 in Nominal, FNPT End Style, 200 psi Pressure, 180 deg F, 5.07 in Inlet to Outlet Length, Brass Body, Stainless Steel Trim, NBR Softgoods, 2 in L x 2 in W x 5.1 in H Dimensions