The 200pcs 9 Sizes Premium Copper Metric Sealing Crush Washers Assortment Kit is a versatile and essential kit for anyone working with sealing applications in industrial, automotive, or household settings. This kit includes a wide variety of copper washers, each designed to provide a tight, leak-proof seal for different sizes of bolts, plugs, and fittings. Here's a detailed review based on its key features:Key Features:200 Pieces in 9 Sizes: The kit includes a total of 200 washers in nine different sizes, covering a broad range of common applications. Sizes include M5, M6, M8, M10, M12, M14, ensuring you have the right size for your needs.Premium Copper Material: These washers are made from high-quality copper, known for its excellent durability, corrosion resistance, and malleability. Copper is also highly conductive and has a natural ability to form tight seals under pressure, making it ideal for sealing applications in automotive, plumbing, and machinery.Flat Sealing Washers: These are flat washers, specifically designed to provide a tight and even seal when compressed. They are often used in areas like oil sumps, plumbing fittings, and any application where leakage prevention is critical.Versatile Applications: These copper washers can be used in a variety of applications, including automotive maintenance (e.g., for oil sump plugs), household plumbing (e.g., pipe fittings), and industrial machinery. They are ideal for sealing areas where a secure, leak-proof connection is needed.Crush Washer Functionality: The washers are designed to crush slightly when tightened, which allows them to conform to the mating surface and create an effective seal. This feature is important for applications where a precise seal is needed under pressure, such as in hydraulic or oil systems.Storage Case: The washers come neatly organized in a plastic case with individual compartments for each size. This makes it easy to store and locate the correct size when needed, preventing loss and ensuring easy access.Pros:Wide Range of Sizes: With 9 different sizes, this kit covers a broad spectrum of sealing needs, making it a convenient all-in-one solution for various projects. The variety of sizes ensures you can tackle a wide range of applications without needing to buy multiple different packs.High-Quality Copper Material: Copper's durability and corrosion resistance make these washers reliable and long-lasting, ideal for both automotive and plumbing use. Copper also provides a superior seal compared to other materials.Effective Leak Prevention: The crush washer design allows the washer to create a tight, leak-proof seal, preventing fluid or gas leaks, which is essential in both industrial and household applications.Convenient Storage: The washers are neatly organized in a plastic case, which makes it easy to find and retrieve the right size when working on projects. This organization helps prevent clutter and loss of washers.Cost-Effective: With 200 pieces in the kit, it offers good value for the price, especially if you're frequently working with sealing applications.Cons:Limited to Copper Material: While copper is excellent for many sealing applications, it may not be ideal for certain extreme environments (e.g., highly acidic or high-temperature conditions). In such cases, other materials like aluminum or steel washers may be more suitable.Not as Strong as Some Alternatives: While copper washers are highly effective for sealing, they may not be as durable or long-lasting as other types of washers (e.g., steel or hardened washers) in high-stress applications.May Require Tightening Adjustment: Since these are crush washers, they require proper torque when being installed. Over-tightening could lead to deformation, while under-tightening could result in an ineffective seal. Proper installation is key.Conclusion:The 200pcs 9 Sizes Premium Copper Metric Sealing Crush Washers Assortment Kit is a comprehensive and practical kit for anyone in need of high-quality sealing washers for automotive, plumbing, or industrial applications. With a variety of sizes, durable copper material, and effective sealing capabilities, this kit offers great value for DIY enthusiasts, mechanics, and professionals.Its versatility in applications, from oil sumps to plumbing fittings, makes it a must-have for those regularly working with seals and fittings. The well-organized storage case adds to its convenience, allowing for easy access and organization.While it may not be the best option for extreme conditions, the copper washers in this kit are perfect for a wide range of general-purpose sealing tasks. If you're looking for a reliable and cost-effective solution for sealing, this assortment kit is an excellent choice.

These washers are good quality and there is a good variety of sizes. Mostly I need for oil changes on a few different ATVs and these are a nice set to have around.