21" Cab Guard Tool Box No Drill Installation Bracket Kit (30122TB) by BackRack®. Finish: Black. This is a set of two bracket pieces that bolt to your truck’s side rail areas, and also to a BackRack Cab Guard rack (if installed). These are a necessary purchase if you are installing a BackRack Steel Cab Guard rack. Reinforced steel construction ensures high strength and rigidity, and a protective layer of black powder coat matches the look and corrosion resistance of the Cab Guard rack itself.