quality copper material: crafted from copper with a melting point up to 1083 degrees Celsius, delivering durability and longevity for longterm use. Versatile and wide application: suitable for various engine types including automobiles, marine engines, generators, machinery, and industrial facilities, making it useful for a broad range of and maintenance tasks. performance and quality: designed to provide reliable sealing and effective leak prevention, with quality you can trust. Convenient package: includes 200 copper crush washers and a sturdy box for easy storage and organization. Practical use scenarios: Automotive maintenance: seal oil drain plug connections during routine oil changes on cars and light trucks. Marine and generator service: seal fuel, oil, or hydraulic connections on marine engines and portable generators. Industrial equipment upkeep: seal fittings on pumps, compressors, and other machinery to prevent leaks.