This is the Hobby Products International (HPI) M Compound Radial Tires Standard Narrow (26mm) Width for Touring Cars and Sedans.
Radial Tread and Medium "M" Compound
Fits Touring type cars from Kyosho, Tamiya, Yokomo and the HPI RS4 using standard width wheels
Fits Standard Narrow 26mm Width Wheels
Two Radial M Compound Tires
Two Grey Foam Insert Strips
Outside diameter: 2-9/16" (2.5") (65mm)
Inside diameter: 1-15/16" (1.9") (49mm)
width: 1-1/16" (1.") (26mm)
Glueing Tires to Wheels with CA Glue Such as GPMR6001.
Glueing the Foam Insert Strip with Contact Cement
26mm Width Wheels
Writing on the sidewall says "HPI Racing" on both sides.
Other versions available:
HPIC4512 4512 M Compound Radial Standard Width
HPIC4513 4513 M Compound Radial WIDE Width
HPIC4540 4540 Super(Soft) Compound V-Groove Standard Width
HPIC4514 4514 Pro(Very Soft) Compound Radial Standard Width
HPIC4490 4490 Pro(Very Soft) Compound X-Pattern Standard Width
HPIC4415 4415 Pro(Very Soft) Compound Slick Belted Standard Width