These are medium rear foam tires for the Tamiya F-1 series cars.

Features: HBR (High Butyl Rubber) medium compound -- similar to black dot compound, higher natural rubber content than stock tires Pre-trued

Includes: (2) Rear tires
(4) pieces of double back tape for mounting
Instructions (for removing old tires and installing new)

Specs: Outer diameter - 55mm
Inner diameter - 30mm
Width - 40mm .
Comments: Highly recommend tire glue in place of double sided tape.