Locking Diamond Tweezers Gemologist Jewelers Watch Tool. This is a new pair of side locking tweezers. They have finely serrated jaws to hold stones and small objects firmly. These offer an improved locking system a superb balance. It measures approximately 6 5/8" (168.4 mm) long. 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.