Soft and casual, our lightest synthetic base layer crewneck is designed for everyday use, providing just the right amount of warmth without adding bulk.Why We Love ItWhen it comes to base layers, we know how hard it can be to find the perfect pick. That's why we designed our L.L.Bean Base Layers to take the guesswork out of finding the right weight, or fabric or fit. When the cold weather hits, this lightweight layer is perfect for casual wear under everything from flannels to winter jackets.