The Libec ALX S4 is a 15.5" long camera slider that features an integrated 75mm ball base with a flat bottom, allowing it to be mounted directly to 75mm bowl fluid heads as well as flat-base heads. When used on tabletop or flat surface using, the slider has a maximum load capacity of 33 lb. For smooth and wobble-free operation, the carriage features eight roller bearings positioned on the rail top and along the sides at angles. A spring-loaded friction knob allows you to adjust slide tension, while a brake knob will lock the carriage in place at any point on the rails. Using a supplied hexagon wrench, you can adjust the pushing force that the ball bearing exerts on the rail.

At each end of the slider, there are 1/4"-20 and 3/8"-16 threads and a rosette for attaching various accessories. If you will be using the slider on the ground or tabletop, the slider features built-in legs with height-adjustable feet to accommodate non-level terrain. For compact storage, the legs fold up against the side of the slider, securing in place using thumb knobs. Unscrewing the knobs completely allows you to detach the legs completely and swap out the 15.5" rail for separately available 32.6" or 47" rail lengths.