Sioux Chief 657-F - Hydra-Rester Commercial Water Hammer Arrester - 1" MIP Thread (15-1/8" Length)Hydra Rester Commercial Water Hammer Arrester 1" MIP Thread (15 1 8" Length) Certified by the American Society of Sanitary Engineering to the ANSI ASSE 1010 2004 Standard Lifetime cycle tested at U. S. Testing Laboratories to withstand 10,000 shock cycles. Factory tested to withstand 500,000 cycles without failure (654 C tested) Hydra Rester male sweat fittings are compatible with press fitting systems, such as Viega ProPress and all push fitting