Tioga Power Block, OS20, 20" x 1.85" Tires
POWERBLOCK OS20 + 60 TPI Casing + UTC Rubber Compound + Wire Bead + OS20 x 1.85 (O.D. 548mm): 15.17oz; 430g Wire bead with a more robust 60 TPI casing, the practice-grade OS20 PowerBlock has all the same tread and rubber features as the S-Spec version.