Extang Tool Box Tonno Truck Bed Tonneau Cover | 32450 | fits Chevy/GMC Silverado/Sierra 1500 (6 1/2 ft) 2014-18, 2500/3500HD - 2015-18, 2019 Silverado 1500 Legacy & 2019 Sierra 1500 Limited L-Channel Rail Bridges the Toolbox-To-Tonneau Gap For Perfect Fit L-Channel Rail also provides a seal against the box Toolbox Tonneaus Fit Most Standard Size Toolboxes, 18-20" Exclusive And Patented All-Climate Tarp Design Adjustable Snaps and Bows For Easy Use In Cold Weather