About This Easy Stacking & Durable Design: With self-aligning nesting boxes and high-performance polymer construction, powder-coated steel corners, and a steel-reinforced lid. Auto-Locking Tool Box: The mechanism engages when the box is dropped into place and has 2 locking points to accommodate most lock sizes and types. Slide Switch: Unlocks the stack and clearly indicates when it is ready for transport. A silicone gasket seals the lid to keep out dust and water. Accessory Rails: Allow adding quick-release accessories for a fully customizable solution. Center Latch: Provides rapid access to tools. Includes 4 bins (2 open top + 2 closed top) and 4 dividers; bins attach to StackTech Bar (TB-B1-A-30, sold separately). Overview Brand : ToughBuilt Material : Plastic Color : Black Product Dimensions : 16"L x 21"W x 7.2"H Water Resistance Level : Water Resistant