The Dirty Dan is a MUD specific DH tire and comes in 26x2.5. It is available in either a Gooey Gluey or a triple rubber compound. Hot ticket would be a Gooey Gluey up front and a triple compound out back. New LST bead technology on this model too. -Triple compound rubber means that the outer knobs are softer for grip and the inner tread is firmer to allow a lower rolling resistance.