Mountain Equipment's Eclipse Beanie is a light, comfy and packable hat that is ideal for under helmet use but just as functional on its own.
Mountain Equipment says:
A low profile, fast drying fleece beanie that fits perfectly under a helmet.
Mountain Equipment's Eclipse Beanie is super light and ideal for fitting under a helmet. The Pontetorto Tecnopile fabric is very stretchy and soft on the skin. The grid pattern on the inner aids wicking if your working hard.