For indoor/outdoor cranes as well as conveyor systems, System P4 exhibits minimal noise and wear at high speeds - even with loads up to 20 lb/ft. There is almost no weight limit due to center links, and each link has same pitch to minimize vibration in radius. Tested outdoors at speeds to 23 fps over distances of 400 ft, carriers have plastic bridges and grooves along surface so that upper run glides smoothly over lower run. Plastic rollers are firmly integrated into sides.