Warm enough to take the edge off, but breathable enough to move in, Rab's Cirrus Flex range is archetypal 'active insulation'. Gear Ed Dan reviewed the Cirrus Flex Vest last year, and still more or less lives in it. So what are the sleeved versions like? Penny Orr and Rob Greenwood find out.
I've been wearing one since December. Pulling a windproof on over the top when you stop ramps up the insulation effect and gives you an instant belay jacket.