Hand Assembled Challenge uses the latest technical materials such as corespun for the inner casing of these tyres. This material produces a very high TPI (threads-per-inch) count to ensure the ultimate in strength, suppleness, and low weight. This casing is then hand glued on to the tread, which has previously been installed and inflated on a rim. This means that when the assembled tyre is inflated, it provides more precise handling, lower rolling resistance, and better grip. Shock Absorbing The best materials have been used to obtain consistent grip over uneven terrain and reduce the vibration feedback to the rider, helping you to maintain grip and control on even the longest and roughest races. The advanced design reduces wheel skipping and jumping over rough surfaces, ensuring efficient grip and helping you to maintain your speed. These tyres also feature a double layer of Challenge’s PPS (puncture protection system) between the tread and casing, to give you confidence when blasting over tree roots and sharp rocks. Technologies: Challenge Handmade Tubulars (HTU): Our Handmade Tubular (HTU) tires perform better than any tubeless system! Therefore, they are raced by all the top athletes and teams in every cycling segment. The latex inner tube we cradled inside the high-quality casing that is sewn shut, forming a soft protective layer for the delicate tube. A base tape is glued over the sewing for protection and to absorb the adhesive later applied to hold the tubular on the rim. The carcass is mounted on a rim, inflated and a special natural rubber tread is precisely glued on top. Puncture protection layers and sealants can be applied to the finished casing, depending on the tubular’s use.