Their hand-tooled "Saddle Leather Belt" is made using only vegetable-tanned butts sourced in the best European tanneries. The natural tanning process takes from 6 weeks to 6 months in order to achieve the necessary thickness and strength. They then naturally tan the leather using oak bark or vegetable tannins to preserve the leather as well as natural oils (from fish/animals or bees wax) to finish it. Every single belt is hand-tooled individually by their artisans. The last step for each belt is the final polishing done by hand using hard natural wax which is necessary to give the belts their "natural light". Featuring a "Chicago style" size adjustment screw system, that Mr.Derk will size for you right after purchase.