20pcs Bonded Sealing Washers 12x4.2x2.8mm Stainless Steel EPDM Screw Gasket

What will I get?
Color: Silver, Black
Material: 304 Stainless Steel, EPDM Rubber
Outer Diameter: 12mm
Inner Diameter: 4.2mm
Thickness: 2.8mm
Package Contents: 20 x Cushioning Gaskets

What is this?
The bonded sealing gasket provides an airtight seal between the bolt or screw and the hard surface.

Are there any advantages of the product?
The 304 Stainless Steel washer is slightly angled but flattened as it's tightened.

How to use it?
Suitable for outdoor or humid environment, strong corrosion and acid resistance.
It can avoid thermal expansion and cold contraction during installation, improve the fastening effect, sealing, dust-proof, and waterproof functions. Also serves as a cushion protecting from vibration.