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 60 PSI. Model Number: RF743-GKSK-D Size: 700×43C ETRTO: 43-622 Bead: Folding Color: Black Sidewall: Brown Weight (g): 490 MAX PSI: 60