Looking for a tire that's more aggressive than the mixte-tread GravelKing? The GravelKing Sk might just be the tire you need for the more hardcore roads. Aggressive knobs, ZSG Natural rubber compound, puncture protection breaker and AX-α special low rolling resistance casing make the Gravelking a go-anywhere tire. And tubeless compatible up to 50 PSI. Size: 27.5×1.90 (650B×48mm) ETRTO: 48-584 Bead: Folding Tire Color: Black Sidewall Color: Brown Weight: 540g Max PSI:  50