CO-AX coaxial centering indicator - Easy machine orientation: by simply replacing the inductor, switch from horizontal to vertical machines and from inner diameter to outer diameter without any other changes. As the spindle rotates, the display stays stationary in your chosen position, giving the operator both hands free to position the worktable precisely. - Quick, precise centering: range 0 to 0.15 with a 0.0005 resolution. This CO-AX tool quickly and accurately centers bore and milling operations on horizontal or vertical machines. When the spindle turns, the scale faces the operator for easy centering. - Shank, capacity, and speed: shank 3/8. Capacity 5/32 to 4-1/4 inch bore or 0 to 4-1/4 inch outer diameter. Spindle speed is 100 rpm; exceeding this speed is not recommended. This is a professional indicator for locating the workpiece center on drill or milling machines (alignment) and for the lateral center diameter. - Center-reading dial indicator: a new measuring instrument that uses a lever to transfer the relative position of the workpiece center to the dial gauge and converts it to angular displacement of the pointer. It is accurate, practical, and clearly visible for finding the relative center of the workpiece, such as the circumference and inner hole.