AMP Terrain Attack A/T A 37x12.50R2037X12. 50R20 AMP TERRAIN ATTACK AT A ALL TERRAIN 37125020 TIRES Brand: AMP Model: Terrain Attack AT A Size: 37x12. 50R20 Part#: 37 125020AMP CA3 Aspect Ratio: 12. 5 Inflated Diameter: 37 Inflated Width: 12. 5 Load Index: 126 Load Rating: E Load Range: 3750 LBS Max Load Max Psi: 65 Ply: 10 Section Width: 37 Service Description: 126R Sidewall: Black Speed Rating: R Tire Rim Diameter: 20 Tire Type: All Terrain Tire Type2: Hybrid AT MT Tread Depth: 15. 5