Dayton hubs were Standard equipment, on the '47-'55 400 series GMC's. Optional equipment on the 450, & 470 series GMC's. 6 stud Motor Wheels were standard on the 450, & 470 series, & a 10 stud Budd Wheel was also optional on the 470 series. These Dayton Adapters were an available Accessory for these trucks. All 400, 450, & 470 series trucks, had the larger, wider fenders, to accomodate the Heavier, wider front axles used on these series trucks.