Truxedo 571701 Tonneau Cover Features: 5 Minute Installation-No Tools Required Automatic Tension Control-Keeps Cover Tight Lifetime Warranty Covers Everything-Even Fabric Low Profile Design Improves Gas Mileage Patented Velcro® Brand Side Sealing System Completely Stores At The Front Of Bed Corner/Weather Seals on Sides Keep Elements Out Custom/Color Applications Available Height: 5.25 Width: 9.50 Length: 98.38 Fitment: 2013/GMC/Sierra 3500 HD/WT Standard Cab Pickup 2-Door/6.6L 6599CC 403Cu. In. V8 DIESEL OHV Turbocharged::Bed Length = 97.6, Bed Side = Fleetside, Dually Bed^^2013/GMC/Sierra 3500 HD/WT Standard Cab Pickup 2-Door/6.0L 5967CC 364Cu. In. V8 GAS OHV Naturally Aspirated::Bed Length = 97.6, Bed Side = Fleetside, Dually Bed^^2013/GMC/Sierra 3500 HD/WT Standard Cab Pickup 2-Door/6.0L 5967CC 364Cu. In. V8 FLEX OHV Naturall...