This Fits Your 2021 GMC Sierra 2500 HD 6.6L Duramax V8 DIESEL A/T RWD Base Extended Cab Pickup Fleetside
Full size assembly image of Pick up box. Exterior trim. (1/1)

Pick up box. Exterior trim.

"AT4". "c". "denali". "g". "m". "sierra". "sle". "slt". 8 ft box. ALL. Center. Outer. Tail gate. W/DENALI. W/MULTI pro gate. W/O Denali. W/O multi pro gate.