Your forehead and ears take the weather first, and at 20 mph in 40°F air that's the part of you that goes numb while the rest of your body is still fine. The AmFIB Lite Skull Cap from Pearl Izumi answers that with a front panel of Polartec Wind Pro, a fabric that blocks oncoming wind while still moving air, so the leading edge of your head stays covered without sealing your whole skull inside a windproof shell.
Everything behind that front panel is thermal stretch fabric — 79% recycled polyester and 21% spandex — and that's the half of the design that keeps this from cooking you on a climb. Heat and moisture escape through the top and rear rather than pooling under your helmet, which is the usual failure point of a plain fleece beanie. The front panel runs 97% polyester with 3% spandex, so the wind protection stretches with the rest of the cap instead of fighting it.
Bulk is the other thing that ruins under-helmet headwear. The AmFIB Lite is cut thin enough to disappear beneath a helmet — no pressure points, no retention dial fighting for space, no loosening your straps a turn to make room. The side panels come down over the ears, and a port in the back lets a ponytail pass through instead of forcing it up against the shell. It's unisex and comes in one size, with enough stretch in the knit to cover a range of head shapes.... Read More
BioViz reflective detailing is worked into the cap and returns light at up to 100 meters, which matters more than it sounds when winter riding happens at either end of a short day. The fabric also carries a UPF 50 rating for bright, cold mornings. If you already own a heavy winter cap and find yourself skipping it on 45°F days because it's simply too much hat, this is the piece that fills the gap — shoulder season through much of a mild winter, layered under a helmet cover when conditions finally turn.
