The RDS 41-Gallon Auxiliary Tank and Toolbox is a diamond-plated aluminum combination auxiliary fuel tank and crossover toolbox. This toolbox includes stainless steel locks to prevent tampering and two cylinders to hold open crowned lid. Each tank comes with a rollover vent, manual sight gauge, baffles, secured fuel fill area, and drain fittings. Optional Diesel Install Kits (sold separately) are available for connecting your auxiliary tank to your truck fuel fill line. For safety reasons, the filler neck on RDS fuel tanks prevents them from being overfilled. Actual usable tank capacity is about 95% of the total advertised gallons due to fuel expansion in warmer climates.• Special Permit issued by the US Department of Transportation (DOT)• Heavy-duty 0.125-gauge aluminum diesel tank• 0.058-gauge aluminum toolbox• 0.187-gauge aluminum mounting brackets• Stainless steel locks• Built-in baffles to reduce movement of contents and sloshing• Reinforced lid• Pressure tested for leaks• Uses include diesel, water, fertilizer oil, bio fuel, combustible fuel• Manual fuel sight gauge• Enclosed fuel fill areaSpecsRDS #: 72773Capacity: 41 gallonsDimensions: 55"L x 18"W x 21-3/4"HToolbox: 48"L x 9"HNotch: 6"W x 5"H Two cylinders to hold open crowned lid Rollover vent, manual sight gauge, baffles, secured fuel fill area, and drain fittings Pressure tested for leaks | 41-Gallon Notched Auxiliary Fuel Tank and Toolbox Combo