I & D Smallwood Vernier Calipers
This is an early 4" vernier caliper marked "I & D SMALLWOOD BIRINGHAM NO. 2290". Made in England, it has both inch and metric markings on one side only. It's in good useable condition with some minor pitting on it, but not rusty now. The brass thumb screw locks down and holds the caliper in place very well. A nice early English machinist tool!