NOMOS Glashütte Tangomat Collection Stainless Steel & Horween Leather 38.3MM Datum Watch. This watch features a stainless-steel case, with curved sapphire crystal glass front and back all on a black Horween Genuine Shell Cordovan strap. The dial is galvanized, white silver-plated with tempered blue steel hands. The movement is the house built Zeta with automatic winding and date indicator. This watch also has an approximate 42-hour power reserve.