PPG2.45/1.8-1 - PLAIN PIN Plug Gauge Go- 2.456 to 2.457 & Nogo-2.479 to 2.480  mm Depth – GO -1.803 to 1.805 mm & NOGO – 1.895 to 1.900 mm (Microsekai) Go-Nogo Gauge Required to check the Cortex 3.5/4.0 Hex Predrilling)