A24R: Aluminum Oxide – Metal & Steel, Stainless. General purpose. Triple reinforced. Electronically Balanced. All 12-14" wheels are automatically balanced during manufacturing. All 12-14" wheels are guaranteed to be less than 3 and 3.5 grams out of balance. CGW wheels are safer, cause less vibration and are more consistent. CGW uses heavy duty fiberglass reinforcement, so our 12-14" high speed wheels meet speed specifications for all machines on the market. Premium 14" A24R, A24T, AC & 16" wheels are triple reinforced (TR) to provide extra safety.