

🔩 Seal the deal with copper precision – never settle for leaks again!
This 330-piece copper washer assortment offers 12 sizes (M5-M20) of flat sealing crush washers designed for automotive, plumbing, and mechanical use. Crafted from high-quality copper, these washers provide superior corrosion resistance, heat dissipation, and load distribution to ensure leak-proof seals. Packaged in a durable, organized case, this kit is perfect for professionals and DIYers seeking reliable, versatile sealing solutions.












| ASIN | B0DJPB3821 |
| Best Sellers Rank | #2,131 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #11 in Flat Washers |
| Brand | Magicave |
| Color | Copper Washers-330Pcs |
| Customer Reviews | 4.7 out of 5 stars 782 Reviews |
| Exterior Finish | Plain |
| Fastener Size | M5, M6, M8, M10, M12, M14, M16, M20 |
| Fastener Type | Washer |
| Grade Rating | Heavy Duty |
| Item Thickness | 1 Millimeters |
| Item Weight | 0.5 Pounds |
| Manufacturer | Magicave |
| Material | Copper |
| Material Type | Copper |
| Metal Type | Copper |
| Model | Copper Washers |
| Number of Pieces | 330 |
| Outside Diameter | M5, M6, M8, M10, M12, M14, M16, M20 Inches |
| Part Number | M5 M6 M8 M10 M12 M14 M16 M20 |
| Screw Head Style | Flat |
| Size Name | M5, M6, M8, M10, M12, M14, M16, M20 |
| Thread Size | M5, M6, M8, M10, M12, M14, M16, M20 |
| Unit Count | 330.0 Count |
| Washer Type | Flat |
J**N
Excellent
Great Quality and Excellent Value! I’m really impressed with this 1100-piece flat washer assortment kit. The 304 stainless steel feels strong and durable — no rusting or bending like cheaper sets I’ve tried before. The variety of sizes (M2–M12) makes it perfect for all kinds of projects around the house, garage, and even light automotive work. The case is well organized, and each compartment is clearly labeled, which makes finding the right washer super easy. Overall, this set offers fantastic quality and value for the price. Definitely a must-have for anyone who works with screws and bolts regularly. Highly recommend!
P**H
WASHER ASSORTMENT
NICE PRODUCT
D**A
Great assortment of washer
This kit comes with everything I need and it still have more left. Great kit at a price you can beat. It is made of stainless steel. Fit over bolt. Work just like store brand. It come with a storage to keep everything organized.
S**C
IT's JUST hardware.
IT's JUST hardware. What can one say? They are washers! SS metal. worked as designed. Last a long time and each cost less than a dime. Every home DIY kit should have one.
J**E
Premium Copper Washers
This copper washer kit is exactly what I’ve been needing for a while. It comes with a wide variety of sizes, and every single one I’ve used so far has fit perfectly—no leaks, no hassle. Whether I’m working on brake lines, oil drain plugs, or other small engine repairs, there’s always a washer in the kit that fits the job. The copper is high-quality and has a good thickness—not the kind that bends too easily or crushes unevenly. Everything came organized in a sturdy plastic case, which makes it easy to find the right size quickly. Honestly, if you’re a DIYer or mechanic, this kit is a no-brainer. Super convenient, reliable, and a great value for the price. I’ll definitely be grabbing another one when I run low.
S**Y
Great price, little thin but seems to work.
Only needed two, but the price of two at Napa was the same price this entire kit. The only thing that I will say about these that I don't love is the thickness. If you're using these as a crush washer for brake lines they work, but they certainly don't have the thickness that a typical crush washer would. I don't know if this will cause issues long-term but I thought it was worth mentioning.
C**T
Very happy
Great product, exactly as described!
C**S
Great deal
More washers than I'll ever use. Worked great bor what I needed them for.
Trustpilot
3 weeks ago
2 months ago