Barbour Case Fair Isle Jumper Cooast Barbour Case Fair Isle Dog Jumper in Cranberry The Best Fair Isle Jumpers, Including The John Lewis 49 Favourite Barbour Lambswool Case Fair Isle Jumper Jules B Barbour Case Fair Isle Jumper In Navy Marl. This crew neck sweater is knitted with a colourful Fair Isle pattern framed by contrast ribbing at the collar, hem and cuffs. Crafted in super soft lambswool, this distinctive piece is finished with a signature flag label at the side seam.