These are Sealed Bearings from HPI Racing. FEATURES: Metal bearings with rubber seals. Designed for use on the HPI Savage 21. YOU WILL RECEIVE: (2) Sealed Bearings REQUIREMENTS: HPI Savage 21 SPECIFICATIONS: Outer Diameter: 16mm Inner Diameter: 8mm Thickness: 5mm jmm 3/22/03 ir/jxs kr4/28/03 &