Silicon nitride is the most popular balls in hybrid bearings as it has only 40% of the density of bearing steel but is much harder giving greater wear resistance. Hybrid bearings are also capable of higher speeds due to the lower centrifugal force generated by the ceramic balls. However, due to the lower elasticity of the balls, the contact area between the balls and the raceway is smaller which causes a higher contact pressure. This can cause the raceways to wear faster. The speed increase for hybrid bearings is approximately 30-40% with adequate lubrication. Hybrid bearings can also operate better with limited lubrication but running speed should be reduced. They are also less subject to ball skidding under high acceleration with a low load.