Starrett PT22288 Dial Depth Gauges Dial Depth Gauges – Each

12″/300 mm Base extension
Lock screw for dial bezel
Lock screw for holding the measuring rod in position
Optional base extensions of 7″ and 12″ (175 and 300 mm) are available to increase the base span on both models
Removable hook attachment permits readings from the edge of a workpiece to edges of slots, shoulders, etc.