AUTO-LOCKING DRAWER – Prevents drawer from opening during transport. DURABLE STAINLESS STEEL RAILS – Rust-resistant to enable smooth drawer opening, closing, and long life. 9” RUGGED RUBBER WHEELS – Conquer any terrain with oversized rubber wheels. QUICK-CONNECT LATCHES – Fast and effortless interlocking connectivity allows you to quickly stack and unstack toolboxes. ATTACHMENT-READY – Aluminum-reinforced corners with attachment interface compatible with STACK PACK™ attachments. 70 LB. DRAWER CAPACITY; 250 LB. LOAD-BEARING CAPACITY – Heavy load capacity for tools, materials, and accessories. REMOVABLE REAR HANDLE – Extends for easy jobsite navigation and removes fully for storage in a covered truck bed when your work is done. IMPACT PROTECTION – Built with an impact-resistant polypropylene body and aluminum-reinforced corners to withstand the toughest jobsite conditions.