Features: The expansion cleanout caps drain plug features adjustable mechanical seal with stainless steel reinforcement, providing leak proof protection for pipes and preventing backflow in plumbing systems. Crafted from corrosion resistant stainless steel and rubber, this sewer caps cover combines flexibility with weatherproofing for year round indoor/outdoor reliability. Ideal for homeowners, professional plumbers, and marine enthusiasts requiring secure winterization of pools, boats, or residential drainage systems. Perfect for sealing cleanout accesses during freeze protection, boat maintenance, or sewer line repairs where watertight performances is critical. Includes a removable allen wrench handle for effortlessly installation and removal, ensuring tight compression without damaging pipe threads during seasonal transitions. Specifications: Component:Stainless steel+rubber Applicable calibers:Approx.4.5-6cm/1.77-2.36inch Applicable calibers:Approx.5.2-6.5cm/2.05-2.56inch Applicable calibers:Approx.6.5-8cm/2.56-3.15inch Color:Black Package Includes: 1pcs Expansion Drain Plug note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you donot mind befores you order. 2.Due to the differences between different monitors, the picture may not reflect the actual color. Thanks for your understandings.