10PCS/Pack 25.5x33x2mm Copper Washer Solid Gasket Sump Oil Seal This pack provides durable copper washers sized for reliable oil sealing. Each washer is a solid copper gasket designed to create a tight, oiltight seal on bolt heads, fittings, and sump areas where a crushable gasket is appropriate. Key benefits Effective oil seal: copper washer material deforms slightly to fill imperfections on sealing surfaces, helping prevent leaks. temperature and oil resistance: copper maintains performance under typical engine and hydraulic oil temperatures. Value and convenience: 10piece pack ensures you have spares on hand for maintenance or multiple applications. Easy to install: simple washer replacement with standard bolts and fittings, no special tools required. Key attributes Quantity: 10 washers per pack Material: solid copper Inner diameter: 25.5 mm Outer diameter: 33 mm Thickness: 2 mm Function: gasket / seal for sump oil and related fittings Compatibility: suitable for applications that use copper washers of 25.5x33x2 mm for sealing threads and joints Applications and use cases Automotive engine oil drain plugs: worn drain plug washers to prevent oil leaks from the oil pan. Sump and engine seals on small engines and generators: seal bolts or plugs in oil sump areas to maintain oil containment. Hydraulic and fluid line fittings: use as a sealing washer for connections that require 25.5 mm inner diameter copper washers, ensuring a leak seal. Installation tips Ensure mating surfaces are clean and of debris before installation. Use one washer per connection and with a washer if the previous one is deformed or damaged. Do not rely on thread sealants with copper washers; the copper gasket should form the seal on its own when tightened to the appropriate torque. This copper washer set provides a practical, reliable solution for sealing oil sump bolts, drain plugs, and compatible fittings. The 25.5x33x2 mm size and copper material balance conformability with durable, oilready performance.