It's a Buff. It's great for neck, face, head and hair. It's comfortable, warm enough and light enough not to get hot in summer (when using as a hair band for example). Also good for wearing on your wrist to keep warm if you're just wearing a tshirt and the weather turns/cools.
I'd happily buy these, well made, functional and looks great.
Get a fleece/thermal one if you're going to somewhere reasonably cold.