These are 2-3/4" Diamond Lite Wheels from Dubro.
FEATURES: Black impact absorbing foam construction pre-mounted on
gray plastic rims.
Diamond tread design.
INCLUDES: Two Wheels
REQUIRES: Wheel collars to hold them on the axle.
May require reaming out the hole to mount on larger axle.
SPECS: Diameter: 2-3/4 OD
Diameter: .178" axle hole
Weight: 14 gr