Our Chromexcel leather is a combination-tanned (chrome, then vegetable-tanned) leather from Horween in Chicago USA. Chromexcel is the original “pull-up” leather, quickly developing character when folded and flexed. The grease that has been impregnated into the leather causes a lovely tonal effect on the surface. This type of leather is perfect for watch straps because it is pliable, water resistant and develops a beautiful patina quickly. Tannery: Horween, USA Temper: Soft Surface: Smooth, semi-supple with a waxy finish Patina: No Water Resistance: Moderate. To ensure longevity, avoid moisture or soaking our straps in water.