Micro 100 Boring Bar, manufacturer part number QBB5-260400.
Specifications: Minimum Bore Diameter: 0.2800 in; Maximum Bore Depth: 0.4000 in; Shank Diameter: 5/16 in (0.3125 in); Overall Length: 2.0000 in; Hand Direction: Right; Neck Diameter: 0.1950 in; Centerline Offset: 0.1038 in; Projection: 0.0650 in; Length from Holder: 0.8530 in; Corner Radius: 0.0050 in.
Coating/Finish: Uncoated. Unit of measure: Inch.