Neck gaiter
A neck gaiter, dickie or neck warmer is neckwear, or an enlarged collar of a garment, that is worn around the neck for warmth. It is usually a closed tube of fabric, often thick fleece, merino wool, synthetic wicking, or knit material, which is slipped on and off over the head (unlike a scarf, which is an open stretch of fabric wrapped around the neck) to cover the entire neck and conserve body heat.