A hard braking zone into a tight turn on packed dirt, then straight back onto the pedals, asks for traction in two directions, and the Challenge Grifo Pro Tubeless Tire answers with a center section that bites for both braking and pedaling. Fast-rolling knobs keep this handmade cyclocross tire moving on dry ground, and the same layout carries it across grass, roots, and rock. A supple Super Polyester casing supports the tread over uneven terrain. What Our Gearhead(R) Experts Are Saying:"My hookless wheelset ran this 38c tubeless with no extra steps, since compliant hookless rims are a listed fit. Once it was set up, I left it on for dry and wet courses alike."