For our Sno base-layer we have used our favorite yarn from Sudwolle, the Nm 1/60, 100% super fine merino wool, 17.5 microns, and added some Creora-Eco-Soft, to make the fabric stretchy. It's a single jersey that's light and breathable. Feels like a second layer of skin. The long sleeved t-shirt has flat lock seams for better comfort and a fitted shape. This Sno piece comes in a box that we have tried to keep as simple and minimalistic as possible, so that you can use it as a small storage box.