4" Screw Clamp for Many Aspects of Woodworking & Carpentry. This is a new screw clamp. This is used for many aspects of woodworking and carpentry. It has a 2 1/2" (62 mm) capacity. The clamp measures approximately 4" x 1" x 2" (101 x 25 x 50 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.