Castelli Nano Flex 3G Arm Warmer Stay Warm Without The Bulk Stay warm and comfy with the Castelli Nano Flex 3G Arm Warmer. Great for cold and dry conditions but also give some extra protection and warmth in wet conditions. They're constructed using Castelli's very own Nano Flex, which is a revolutionary fabric that is water repellent, thermal and breathable. They also feature double-sided silicone grippers that help keep your warmers in place. Make no compromise in comfort and performance with the Castelli Nano Flex 3G Arm Warmer. FEATURESNano-Flex fabric water repellent thermal and breathable>Flat-lock stitching with a single seam Double-sided silicone grippers to keep warmers in place Sizing Size Small Medium Large Extra Large XX-Large XXX-Large Chest35 1/2-3737-38 1/239-4141-4343-4545-47Waist29 1/2-31 1/231-3333-35 1/235 1/2-37 1/238 1/2-40 1/241-43Hips36 1/2-38 1/238-4040-4242-4444-4646-48Inseam31 1/23232 1/432 3/43334 3/4 | Castelli | Flex 3G Armwarmer Men's | Size Medium In Black