ACER Racing World Champion Ceramic Nitride Pro Series RC ball bearings and Ceramic differential balls are the fastest, lightest, smoothest and hardest balls in the industry. We have full bearing kits for Associated , CEN , Corally , GS Racing , HPI , Hot Bodies , Jammin , Kyosho , Losi , Mugen , OFNA , Schumacher , Serpent , Tamiya , Traxxas , Trinity , XRay and Yokomo RC cars and trucks. We are the winningest bearings on the planet. Race Hard.