Watch Back Case Opener For Watch Repair. This is a new watch back case opener. Great for removing pressed on backs on all watches. Will open the most difficult watch backs. It measures approximately 5 1/4" x 5/8" (133.3 x 16 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.