This is a Package of Red S-10 Silicone O-Rings for Hobby Use. These are used in shocks, absorbing vibration, and many other uses. FEATURES: Silicone construction. YOU WILL RECEIVE: Six S-10 o-rings. REQUIREMENTS: Nothing. These are direct replacement parts. SPECIFICATIONS: Inner diameter: 10mm (0.40") COMMENTS: These o-rings are not limited to use only in HPI vehicles. cmc 03/06/02ir/kh&