Comfortable, durable and undeniably classic, the flat-lasted Helix combines elemental yet refined features to yield one of our most popular shoes. With a highly adjustable lace-up construction, padded tongue and relatively symmetrical profile, the Helix is perfect for guides, advancing climbers and anyone prioritizing all-day comfort. SIZE OPTIONS : 39 - 47 (half sizes); 48-50 (whole sizes) WEIGHT REFERENCE : 215g; 7.6oz (1/2 pair size 40) UPPER : 1.8mm Suede MIDSOLE : Nylon 1.4mm Full Length OUTSOLE : VibramA(R) XS Edge (3.5mm) LAST : FF - Flat Profile, Slightly Asymmetric PROFILE : Flat SYMMETRY : Slightly Asymmetric CLOSURE : Lace PRIMARY MATERIAL : Leather SOLE RUBBER : VibramA(R) XS Edge