AUTO-LOCKING DOOR - Prevents door from opening during transport ATTACHMENT-READY - Compatible with STACK PACK attachments QUICK-CONNECT LATCHES - Fast and effortless interlocking connectivity allows you to quickly stack and unstack toolboxes 70 LB. LOAD CAPACITY - Heavy load capacity for tools, materials, and accessories IMPACT PROTECTION - Built with an impact-resistant polypropylene body and aluminum-reinforced corners to withstand the toughest jobsite conditions LARGE CABINET SPACE - Ideal for larger tools like rear-handled circular saws ONBOARD SECURITY BAR - Locks door to prevent theft and stows between use FULL RANGE COMPATIBILITY - STACK PACK toolboxes, organizers, accessory cases, and toolbox attachments are endlessly configurable across the full STACK PACK system ONE-YEAR WARRANTY - Register your new products and get a one-year limited warranty on your FLEX STACK PACK toolboxes and organizers