These high-quality Rubber Shielded Ball Bearings make an ideal replacement part for your ARRMA vehicle.FeaturesPremium ball-raced bearings for ultra-smooth operation in all conditions - Precision manufactured for fast and easy fit and consistent servicing - Manufactured to consistent tolerance for safe and secure assembly - High-quality rubber shields for enhanced protection against the elements - Keeping dirt, water, and dust out, and lubrication in, means more time bashing and less time wrenching SPECIFICATIONS: Inside diameter: 15mm Outside diameter: 21mm Thickness: 4mm Includes2 x Ball Bearing 15 x 21 x 4mm