American Sun USA Made 1/2" End Mill 3" Extension Holder USA Made MOD-910-3 End Mill Extension today most companies even Grobet

today most companies even Grobet express the compound angle formed at the peak or head of the countersink which in this case is 100 degrees

012” radius

0005" Bore Gauge  The Holmike is new and may be a little stiff as it has been stored from some time and protective grease has dried comes with instructions

small grooves

American Sun USA Made 1/2" End Mill 3" Extension Holder USA Made MOD-910-3 End Mill Extension today most companies even GrobetAmerican Sun 1 2" End Mill Holder 3" extension . MOD 910 3. Manufactured in the US (a small American firm that made the highest quality tooling. This top of the line tool is for all CNC or standard milling machines, manufactured of high quality alloy materials, heat treated to 60RC and precision ground for accuracy.