Set of 4 Mint And New Professional Watchmaker Knife. This is a new set of 4 watch back case opening knives. They are great for removing pressed on backs on all watches. You receive: One case knife that measures approximately 6 1/4" (159 mm) 3 Case knives that measure approximately 5 1/4" (133.3 mm). We work hard to update our descriptions and pictures of our merchandise. As part of a process of ongoing innovation by our suppliers, newer versions of the item shown may be shipped before we are able to complete an update. As a result there may be a slight variation in color and design.