Pack Bike Cap. Packable technology has been applied to a must-have accessory for cyclists. Enjoy a classic road cycling cap with top-notch features to wear under a helmet. An ideal cap to maintain body temperature in mild weather conditions. Designed for the high performance accessories seeker, the pack concept by BUFF? is the base of our most technical caps and visors. Developed in our design labs and fully tested by top BUFF? ambassadors, our packable designs can be folded inside a hand, twisted and packed into the smallest pocket without losing its shape once released. Design: Patterned. One size.