The North Face Men's First Trail UPF LS Shirt is a lightweight layer for hiking. Button up, head out. This shirt is designed for the trail, with UPF 40+ sun protection and FlashDry-XD technology built right into the fabric. No sunburns here, plus all that sweat gets wicked away and dries fast, leaving you comfortable, regardless of how many more miles left to hike. Featuring a back yoke with mesh underlay, it's even more breathable as body heat is allowed to escape.