An ultra strong, high impact, composite material that is at the heart of our revolutionary new geartrain. KARBONITE composite gear train has eliminated lash and slop forever. They are less likely to strip under the shock and loads that would usually break standard gears. Found in all the "HD" (Heavy-Duty) and "HB" (Heavy-Duty Ball Bearing) servos. "Karbonite" gears are four times stronger than our standard nylon gears and offer virtually ZERO wear; even after 250,000 cycles when tested! The result, you get better control with KARBONITE gear technology.