Fits the following 2021 GMC Sierra Submodels:
- CREW CAB 1 TON CHASSIS 137.0, CREW CAB 6'6" BOX 1 TON, CREW CAB 6'6" BOX 3/4 TON, CREW CAB 8' BOX 1 TON, CREW CAB 8' BOX 3/4 TON, EXTENDED CAB 6'6" BOX 3/4 TON, EXTENDED CAB 8' BOX 1 TON, EXTENDED CAB 8' BOX 3/4 TON, EXTENDED CREW CAB 1 TON CHASSIS 161.5, REGULAR CAB 1 TON CHASSIS 137.0, REGULAR CAB 1 TON CHASSIS 161.5, REGULAR CAB 8' BOX 1 TON, REGULAR CAB 8' BOX 3/4 TON | 8 Cyl 6.6L Diesel