Built for medium to heavy-duty trucks, Buyers Products Heavy Duty Diamond Tread Aluminum Step Box provides framed steps with convenient built-in storage space. These boxes are a great multi-purpose solution for larger vehicles like Class 8 trucks. A universal design fits all major semi-truck brands including Peterbilt®, Kenworth®, International®, Freightliner®, Western-Star®, Volvo®, and Mack®. The rugged design incorporates a smooth aluminum body with a diamond tread aluminum door for great durability and looks. The locking compression latch keeps tools protected from weather and theft. A built-in rain gutter and automotive bulb seal protect gear from moisture and grime. Replaceable grip strut steps provide superior traction in inclement weather and can be swapped out as they wear down. Available in multiple sizes to suit a variety of applications.