Steel Underbody Boxes Constructed with heavy duty steel and coated with black or white corrosion and abrasion resistant powder coated finishes, LUND's underbody boxes provide heavy duty truck drivers with a secure, convenient storage solution. Designed with weatherproof gaskets to seal out dirt and moisture, these boxes also have commercial grade lockable stainless steel T-handles to secure contents. Available in three sizes to fit most heavy duty trucks, our underbody boxes offer ample room to store valuable equipment and bulky tools. All boxes are 100% assembled in the USA and are backed by LUND's Limited Lifetime Warranty.