Replaces Standard Railmount Hardware. Allows Toolbox to be installed flush against BackRack(TM). Eliminates gap between Toolbox and Backrack. Allows Toolbox to be installed without drilling into truck bed. Standard 21 inches. Optional 31 inches available. Tonneau Cover Hardware Kit; Wide Top; 2019-2021 Chevrolet Silverado 1500 Tonnopro - Hard Fold American Tonneau - Hard Tri Fold Tonnopro - Tonno Fold American Tonneau - Soft Tri Fold Trail FX - Soft Tri Fold BesTop - EZ Fold Extang - Trifecta ALX Enthuze - Hard Tri-Fold RTX - Soft Fold Enthuze - R-Series Enthuze - Hard Tri-Fold Wide Top Enthuze - Soft Tri-Fold Extang - Solid Fold Extang - Trifecta Gator - Hybrid Gator - Soft Tri Fold Ionic - Tri Fold Lund - Genesis Tri Fold Pro EFX - Tri Fold Rugged Cover - E Series Vinyl Folding Rugged Cover - Hard Folding Rugged Cover - Premium Vinyl Folding Advantage Truck Acc - Hard Hat, 2019-2021 Chevrolet Silverado 1500 Tonnopro - Hard Fold American Tonneau - Hard Tri Fold Tonnopro - Tonno Fold American Tonneau - Soft Tri Fold Trail FX - Soft Tri Fold BesTop - EZ Fold Extang - Trifecta ALX Enthuze - Hard Tri-Fold RTX - Soft Fold Enthuze - R-Series Enthuze - Hard Tri-Fold Wide Top Enthuze - Soft Tri-Fold Extang - Solid Fold Extang - Trifecta Gator - Hybrid Gator - Soft Tri Fold Ionic - Tri Fold Lund - Genesis Tri Fold Pro EFX - Tri Fold Rugged Cover - E Series Vinyl Folding Rugged Cover - Hard Folding Rugged Cover - Premium Vinyl Folding Advantage Truck Acc - Hard Hat, 2019-2021 GMC Sierra 1500 Tonnopro - Hard Fold American Tonneau - Hard Tri Fold Tonnopro - Tonno Fold American Tonneau - Soft Tri Fold Trail FX - Soft Tri Fold BesTop - EZ Fold Extang - Trifecta ALX Enthuze - Hard Tri-Fold RTX - Soft Fold Enthuze - R-Series Enthuze - Hard Tri-Fold Wide Top Enthuze - Soft Tri-Fold Extang - Solid Fold Extang - Trifecta Gator - Hybrid Gator - Soft Tri Fold Ionic - Tri Fold Lund - Genesis Tri Fold Pro EFX - Tri Fold Rugged Cover - E Series Vinyl Folding Rugged Cover - Hard Folding Rugged Cover - Premium Vinyl Folding Advantage Truck Acc - Hard Hat ...See Application Guide for Additional Fitments
