Ideal Vacuum | ISO 63 One Sided Centering Ring Stainless Steel with Viton O- Ring, NW-63 Vacuum Flange Size, Typically Used With 2.5 Inch O.D. (63.50 mm) Tubing
2.5" x 20" Stainless Steel Sump O-Ring
Uxcell 2.5" Silicone Rubber Gasket Flange O-Ring for Vacuum Clamp White 2 Count - Walmart.com
V1020-2.5X20 Metric O-rings
Everbilt 2-1/2 in. x 2-1/4 in. x 1/8 in. Buna Rubber O-Ring 837478 - The Home Depot
16mm x 21mm x 2.5mm O-Ring (8 pieces): Amazon.com: Industrial & Scientific
Silicone O-rings 17 x 2.5mm Minimum 10 pcs - OringsandMore