The Heavy Duty Portable Rolling Tool Case from GEARWRENCH is resistant to chemicals, dust, humidity, and harsh temperatures (below 27.4 degrees F and above 194 degrees F). The wheels are self-oiling and free-running, tested to exceed 60 miles of travel. The tool case features stainless steel padlock protectors, corrosion-proof metal hinges with lid-stay features, and four durable trays with additional built-in foam protections (two convoluted-style and two with platform-style). The trays measure 20-1/4" by 13-1/2" and can accommodate two small GEARWRENCH modular sets or one large modular set.