The straps are made of felt: 100% wool, heavily fulled to create a dense, thick, and highly durable felt textile. The name BOX CLOTH originates from the 1800s, when cars had not yet become widespread. Coachmen, who drove the horse-drawn carriages that were the primary means of transportation at the time, used this material for warmth like a coat, lap blanket, or scarf. The seat where the coachman sat was called the Box, Box Seat, or Coach Box, which is how the name came about. BOX CLOTH differs significantly in construction from standard ALBERT THURSTON suspenders. Standard suspenders are sewn in place at the adjuster used to change the strap length, whereas with BOX CLOTH, shortening the straps leaves the excess material hanging down. The excess strap can be cut to shorten it after adjustment. Because it is felt, it will not fray. This is a distinctive feature that sets it apart from other items. It is truly ALBERT THURSTON's signature product and the most classic item we recommend.