The Arcteryx Covert Cardigan. Worn as a standalone piece or an effective midlayer, the Covert Cardigan is a performance fleece jacket with a casually textured, heathered look. Simple, elegant design has modern sweater styling, clean lines and a trim fit. Arc’teryx developed Alpenex™ heathered fleece fabric to create an approachable technical jacket with the elegant look of wool. The polyester fabric has a brushed back knit that is engineered to provide versatile warmth and comfort.