Space-Trac's™Mobile Shelving Systems are designed to store up to 75 percent more material in the same footprint as conventional shelving. The high-density, light-duty modular storage systems feature a sliding carriage design that can slide to create an aisle in the side-by-side model, shelves or a wall behind the lateral model or to slide a unit forward in the pull-out model. Each of these models comes in total storage weight capacity options of 450, 750 or 900 pounds, measures from 60" to 72" tall and has shelves from 15" to 36" deep. Optional pegboards and tool holders are available for the heavy-duty pull-out model. Space-Trac mobile carriages are also available to retrofit existing shelves. Pricing varies depending on the model and weight capacity, ranging from $118 to $188 per unit.