These are 2-3/4" Super Lite Wheels from Dubro. Black impact-absorbing foam construction pre-mounted on gray plastic rims. Rib tread design. Two Wheels Wheel collars to hold them on the axle. May require reaming out the hole to mount on larger axle. Diameter: 2-3/4 OD Diameter: .178" axle hole Weight: 12.73 gr tjt 011002 ir/kh &