General description Set of 4 shower door rollers, including 2 upper rollers and 2 lower rollers. Designed for both flat and curved sliding shower doors. Features adjustable wheel position for customized fitting. Constructed from durable zinc alloy with smooth ball bearings and wear-resistant nylon wheels. Technical specifications Wheel diameter: 23 mm. Upper roller: no buffer spring. Button rollers equipped with cushioned springs for secure mounting.