The SliderPLUS PRO Medium from edelkrone uses the same unique tracking mechanism found in the SliderPLUS V2, which allows the rails of the slider to move with the camera when mounted on a tripod. This gives the slider 19.2" of sliding range in a unit that is only 17.2" long. Featuring a stronger structure that the SliderPLUS V2, the PRO Medium can support higher load capacities up to 30 lb pounds, for use with professional camera setups. Its compact size makes it ideal for travel, as it takes of up less room in your camera bag than other sliders with a similar sliding range.
The tracking system works by having two thin bands that are connected to each side of the mounting plate and base plate. When placed on a flat surface, the base plate travels in the opposite direction of the mounting plate. This yields results similar to traditional sliders. To take advantage of the design, the SliderPLUS PRO needs to be mounted to a tripod. When mounted on a tripod, the movement of the base plate is restricted, causing the rails to move through the base plate in the same direction as the mounting plate. This uses the length of the rails twice, doubling the sliding range.
With traditional sliders, you're often limited to the amount of dolly in/out you can do, because the slider itself usually will end up in the shot eventually. With the SliderPLUS PRO, the rails are also retracting backwards with the camera, allowing for longer dolly in/out shots. A lock mechanism can be engaged to keep the slider from moving if the tripod becomes unlevel. When locked, you can safely move your setup around without having to remove your components from the slider.
The slider provides a 3/8" threaded hole at the bottom of the base plate for attaching to tripods, and provides a retractable 3/8" screw for mounting a flat base tripod head to the mounting plate.