The Easy-Fit Shape molding process pre-forms each tire into a rounded profile before it ships. This keeps the bead from collapsing into the rim channel during installation, which is what makes handmade tires notoriously difficult to mount. The second bead clears the first bead position more easily, reducing the wrestling match that normally accompanies tubeless setup on tight-fitting rims. You'll still need tire levers for the final section, but the overall installation process requires less force than previous Challenge TLR models.

Hookless rim compatibility covers the full size range from 28mm through 38mm, addressing both traditional road rims and wider modern standards. The tubeless-ready bead seats on both hooked and straight-sidewall profiles without pressure restrictions, though Challenge recommends their Smart Tubeless Sealant for optimal air retention. Width selections start at 28mm for frames with tight clearances, extending to 38mm for riders prioritizing comfort and puncture resistance over outright speed.

The XP designation places this tire between Challenge's race-focused Strada Pro and their gravel-specific Strada Bianca, occupying the space where most training happens—on pavement that's rougher than you'd choose for racing but smoother than gravel. If you're currently running 28mm race tires year-round and wondering whether upgraded puncture protection is worth the weight penalty, the 4 Stagioni answers that question when you avoid your third flat of the season on the same debris-covered descent.