DefyThe Defy climbing shoe was designed to have a comfortable fit and a modest amount of performance. Perforated vegan synthetic upper & breathable. The Defy is one of the best selling climbing shoes in the world. Anatomical fit that is great for beginners and advanced climbers coupled with great looks make it a no brainer for a first time or repeat buyer. The Synthratek VX upper and Agion Antimicrobial liner ensure lasting comfort and odor protection.