Micro 100 Boring Bar, manufacturer part number PR-230750.
Specifications: Minimum Bore Diameter: 0.2520 in; Maximum Bore Depth: 3/4 in (0.7500 in); Shank Diameter: 5/16 in (0.3125 in); Overall Length: 2-1/2 in (2.5000 in); Hand Direction: Right; Neck Diameter: 0.1500 in; Centerline Offset: 0.0738 in; Projection: 0.0800 in; Tooth Width: 0.0670 in; Corner Radius: 0.0080 in.
Coating/Finish: Uncoated. Unit of measure: Inch.