20mm / 0.75in O-Ring S90RG2-024S90RG2-024 Size: 20mm / 0.75″ Compatible With: Air Bushings, Metric S302001 – 20mm I.D. Compatible With: Air Bushings, English S301901 – 0.75″ I.D. Specifications Units: US METRIC Title Specifications SKU S90RG2-024S90RG2-024