The VERSASTACK™ System Tower includes 3 units: Bottom mobile unit, middle deep tool box and top organizer. All units can stack on top of each other, secured via durable side latches. All 3 units are IP54 dust and water resistant Metal-plastic telescopic handle on mobile unit that leans backwards to allow for maximum volume storage. Rolling unit load capacity is 66-lbs, and 110-lbs when stacked. The VERSASTACK™ system is a flexible platform that allows for many different combinations based on user needs. All units stack on top of each other and connect with durable side latches for easy carrying and safe stacking.