Stop noisy pipes from banging with the Sioux Chief Mini-Rester 1/2 inch. MIP Thread Straight Water Hammer Arrester, which can also be used to help reduce strain on plumbing system joints. This straight water hammer arrester features a 1/2 inch. Male iron pipe connection that can be installed vertically, horizontally or at any angle in between on new rough-in or retrofit installation with 1/2 inch female iron pipe fittings. Water hammer occurs when the flow of moving water is suddenly stopped by a closing valve. If no measures are taken to control it, expensive fixtures and appliances within the plumbing system may become damaged. This can lead to fractured pipe joints, leaking valves, burst laundry hoses, and premature failure of water heaters and other appliances. Water Hammer ArresterInstalls anywhere needed in the plumbing systemReduces strain on plumbing system jointsFor hot or cold pipingFor hot or cold piping