The Relix uses Maxxis` lightest and most supple 170 TPI casing (ONE70) along with SilkShield puncture protection, which protects both the sidewalls and the underside of the treadDC - Dual Compound tread provides a lower rolling resistance center paired with extra grip for the cornersSS - SilkShield offers bead to bead puncture protection covering the tread as well as the sidewallsStandard700x23622FoldBk/Blk145205170DC/SSNo