The Starrett 5005 Electronic Caliper is built with extra long jaws that are 12" (300mm) in size. The caliper is ideal for applications requiring precise outside dimension or inside dimension measurement in tight spaces that standard calipers can not reach. Hardened stainless stell construction for long life. It also offers tight, smoothly fitted slides for maximum accuracy and easy adjustment. Long Jaw Caliper, 0-24" (0-600mm) Range; 12" (300mm) Jaw Depth adjustment.