The all-new ACE AF1 HOLLOWS feature a hollow axle and kingpin, making for the lightest AF1 to date. The AF1 is carefully manufactured using our proprietary casting process. Years in development, the ACE AF1 has a 70% increase in the aluminums structural integrity, making it the strongest cast truck on the market. ACE AF1 Truck Sizing: 22- 7.75″ axle 33- 8.0″ axle 44 – 8.25″axle 55- 8.5″inch axle 60 – 8.75″axle 66 – 9.0″axle 77-9.5″axle 80 – 10.0″ axle DETAILS Sold as a set of 2 Hanger width: 5.6 (143mm) Truck height: 2.1 (53mm) Manufactured with high-quality AA 356.2 alloy using our own proprietary casting method True T6 heat-treated baseplates and hangers SAE 4140 steel alloy HOLLOW axles, oversized to eliminate bearing wobble Patent pending rethreading axle nuts – no more damaged axle ends! Durable Hand-poured 96a urethane pivot bushings for better response Refined suspension for a cleaner turn Top Bushing: 12mm tall | 91a hardness Bottom Bushing: Bottom 14mm tall | 86a hardness Machine-faced hanger ends for precise bearing contact