The shoe's unique upper has an envelope structure that lets you slip your foot right in, similar to what you would find on a wellie. When on, the envelope can be folded two ways. Fold it to your medial side and you'll have a weatherised, water-resistant shoe to help keep your foot dry. When the weather heats up, fold the envelope to your lateral side and take advantage of its perforated design to help keep you cool. A rectangular sandal strap wraps from the heel around the ankle, helping support your foot with every step. Embroidered patches around the ankle and toe provide additional support, while helping to resist abrasion.