The SM-S4303R is a standard-sized servo that has been built by SpringRC specifically for continuous rotation, making it an easy way to get your robot moving. It features two ball bearings on the output shaft for reduced friction, and it offers easy access to the rest-point adjustment potentiometer. This is the strongest continuous rotation servo we carry: 4.8 kg-cm (67 oz-in) and 70 RPM (no-load) at 6V.