Black anodized, 1-1/4" bore, American pattern wheel hubs come complete with 1/4" hardware and are drilled and tapped for both 1/4" & 5/16" bolts. Wheel hubs come complete with 1/4” hardware and are drilled and tapped for both 1/4” & 5/16” bolts. These hubs are made of aluminum and have an approximate outer diameter of 3". 3 bolt pattern on a 2-1/2" bolt circle Shoulder diameter- 1-3/4"