A roller of a support arrangement for a rotary milking platform, where the support arrangement includes a first rail member fixedly connected to the rotary platform, a second rail member stationarily arranged in a position below the platform, and a plurality of rollers arranged in a vertical space between the first rail member and the second rail member. Each roller includes a peripheral surface comprising a contact surface to be in contact with a contact portion of the first rail member and a contact portion of the second rail member. The peripheral surface of the roller includes two beveled surfaces arranged at opposite sides of the contact surface which are located at a smaller distance from a rotary axis of the roller than the contact surface.