The International Durowe 7528-1 watch movement was produced in limited quantities in 1973, with 2000 units manufactured. This movement is characterized as a chronometer and was used in the Speedmaster 125 model. Its functions include an automatic chronograph with 60-second, 60-minute, and 12-hour counters, cam switched center-minute and second hands, sub-second hand, quickset date, shock protection, automatic winding system, and calendar feature. The International Durowe 7528-1 movement was utilized during the approximate period of 1974.