classic, vintage 4-piece precision machinist small hole gauge set. This split-ball type bore setup is engineered for measuring the exact internal dimensions of small holes, slots, grooves, and recesses when paired with an outside micrometer.

Product Features & Kit Sizes:

Complete 4-Piece Set: Covers a comprehensive measuring range from 1/8" to 1/2" (.125" to .500").

Precision Smooth Adjustments: Extra-long knurled handles provide an ergonomic grip, while the bottom tension knobs turn smoothly to expand the split-ball measuring tips perfectly against internal walls.

Premium Storage: Comes housed in its original blue vinyl fold-over organizing sleeve to protect the precision tips from bench dings or tool-chest rattle.