Roller screws or also named planet roller screws are applied if ball screws cannot pick up the load or the dynamic. Instead of balls roller screws have rollers for load transmission so the number of contact points between nut and screw are much higher than in ball screws. Also through the lost of the ball reflection like in ball screws a higher dynamic and speed is realizable. Roller screws can be assembled for ulta-high precision applications (< 3µm) in case of preload of the screw .