Tufo 700X21 C S33 Pro Tubular-Clincher Tire Provides the ride quality and rolling resistance of a tubular tire but mounts to a regular clincher rim. Fine tread pattern contributes to low rolling resistance and good ride quality. Puncture resistant ply. Inflates to 8-12 bar (115-175 p.s.i.) 60 T.P.I. / 335