Thank you for viewing. This is a The North Face Flight Series long sleeve shirt. It's a long-sleeved T-shirt that's comfortable to wear. How about it as a lightweight layer for winter training, running, or mountain climbing? I've rated the condition as is, as there are no issues with use. ♦︎♦︎Instant purchase welcome♦︎♦︎ I'm open to price negotiations, within reason. Thank you very much.