The Avid 13x25x6 Ceramic Engine Bearing offers the maximum performance and reliability to your racing engine at an unbeatable price. The bearing specs are Abec3, 11 G3 Si3N4 Ceramic Balls, PA66 with 30 Glass Fiber Cage, and Chrome Steel 52100 Rings. It has no seals to allow for proper lubrication from the oil in your fuel. A ceramic engine bearing can allow most RC engines to spin an extra 500 rpm with less drag and the life of the bearing is far greater than a steel bearing. Another benefit to ceramics is the weight difference in the balls allowing for less rotating mass.
If your engine is not listed below, please check with your manufacturer first to see what size you require.