The SS was the pioneering choice and remains the optimal selection for a smooth center tread gravel tire, delivering exceptional cornering grip. The TLR models are Tubeless Compatible up to 60 PSI Ideal for gravel, dirt, and rough pavement Smooth, diamond pattern center with side knobs ZSG Gravel Compound (Zero Slip Grip) - Low rolling resistance, consistent in hot and cold temperatures, with strong grip on or off-road TuffTex Casing - High thread count casing featuring bead-to-bead protection that&';s strong yet supple BeadLock Bead - Designed to work with hookless and hooked clincher rims, easily installed with floor pump, and provides additional rim protection Available in Black Tread and Black or Brown Wall Colors TLR and Hookless Compatible Folding (Aramid) Bead New ECO-Friendly packaging made from recycled materials Tire Diameter: 27.5" (650b) ISO Diameter: 584 / road / 650b ISO Width: choose; 38mm, 43mm, or 48mm Intended Use: Gravel Labeled Size: choose; 650b x 38, 650b x 43, or 650b x 48 Flat Protection: Tread and Sidewall Max Pressure: 60psi (tubeless); 80psi (tubed) Tire Bead: Folding Tire Type: Tubeless Ready Clincher Color: choose; Black Tread/Black Sidewall, or Black Tread/Brown Sidewall