EXCLUSIVE AT NET-A-PORTER. The alpaca-blend used to create Reformation's cozy 'Tatum' sweater has a low environmental impact - the wool is sourced from a family-owned herd, where each animal is given an acre of grazing land, in turn allowing for grass regeneration. It has a relaxed silhouette, crew neckline and fitted cuffs. The beige shade goes with almost everything, too.