Description: Specification: - Application: Use on 4" 6" 8" Vernier or Dial Caliper for Dimension over 0.375" - Material: Alloy Steel - Shape: Conical - Diameter: 9.5mm / 0.375" - Length: 55mm/2.17" - Groove Width: 4m/0.15" - Adapts to most 4", 6", 8" digital / dial calipers. Features: ? Designed for dial, vernier, and digital calipers to measure centerline distance. ? Sold in pairs, these gages quickly adapt to most calipers. ? Centerline measurements read in exact figures. ? The 60 degree conical probe fits snugly into holes. ? Constructed of high quality alloy steel hardened to 50 RC, black oxide finished. ? Each probe has two small holding nuts and is supplied with a allen wrench. Package Included: 1 Pair of Center Line Gage(Caliper in Photo Not Included) 1 x Allen Wrench