Terramar Sports Boy's Kids Thermasilk Glove Liner M Black. Over forty years ago Terramar was the first company to introduce silk performance base layer products. Thermasilk® is still a going strong. The Thermasilk Sock Liner offers a natural super soft touch and feel with all the technology you need. The result is a breathable lightweight liner that keeps you warm, dry and comfortable for all your outdoor adventures. The tradition continues.