AIVOOF 4" Metal O-Ring, 2 Pack 304 Seamless Welding Stainless Steel Rings Heavy Duty Smooth Solid Multi-Purpose Big Ring for for Crafts, 10mm x 80mm: Amazon.com: Industrial & Scientific
Amazon.co.jp: Washers 10Pcs Red Silicone Ring Gasket 4mm Outer Diameter 15- 80mm Silicone O-Ring Gasket Food Grade Rubber O-Rings for Fastening and Seal, Easy to Use (Size : OD 33mm CS 4mm) :