The 200 Oasis Men's Long Sleeve Crewe Top is icebreaker's best-selling base layer - a versatile active top for year-round layering and everyday comfort. The soft, 100% merino jersey fabric is breathable, stretchy, and odour-resistant, and flatlock seams provide chafe-free comfort. Our versatile, go-anywhere shirt made from breathable 100% merino wool jersey, the 200 Oasis Long Sleeve Crewe is our best-selling base layer top.