The Starrett 3089 provides precision two-point bore measurement with .0005" resolution and tungsten-carbide measuring faces.

The two-point measuring system allows operators to evaluate diameter as well as bore conditions such as ovality and taper, rather than reading diameter alone.

Choosing a Range

The .7"–1.5" model covers the important small-bore range; the 2"–6" model is the general-purpose professional choice and ships with a 2" extension and 6" probe depth. Both are the same 3089 platform with identical resolution, contacts and grip.

Measurement and Operation

Laser-marked anvils simplify setup and selection — a practical advantage when several sizes are in the case and the markings on conventional anvils have worn. The non-slip insulating grip improves handling and limits heat transfer from the operator's hand.

Applications

General-purpose professional bore inspection in machine shops, toolrooms and quality-control departments.