Shaviv 153-29005 F Blade Holder has an external thread M7 to receive all “F” countersink blades.
Micro Finishing, Shaviv Deburring Tools by Vargus
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Shaviv 153-29005 F Blade Holder
Shaviv 153-29005 F Blade Holder
$9.30
FX - 4 Wide Field Stereo Microscope
FX - 6 Extra Objective Lens .3X 



