While its serial number dates it to 1956, this typewriter was made for the 1957 model year. The easiest way to determine whether your Royal Quiet Deluxe was made for 1957 is by looking at either the keyboard, or the ribbon carrier. If the carrier is made of more than one part, it is from the 1957 model year or later. If the keyboard has 1/! and =/+ keys it is also a 1957 or later model.