Replacement Seal for Fleck 3/4" and 1" Stainless Steel Bypass Valve - Fleck Part # 11726 Replacement seal for leaky bypass valves This is the only replaceable seal and will typically fix all leaks around the bypass handle Works with both the 3/4" and 1" bypass valves used on Fleck 5600, 2510, 9000, 9100, and more Allows you to fix leaks without replacing and replumbing a new bypass valve Fleck part# 11726