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21 Century Manufacturing Counterbore Set 300 Superbore USA Vintage For Sale

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21 Century Manufacturing Counterbore Set 300 Superbore USA Vintage:
$300.00

Counterbores with the associated drill bit for counter boring holes for cap head screws. Vintage 21st Century Manufacturing Superbore Set 300. They don’t make these anymore in this set! Looks like they have never been used, but they show their age a little with a bit of patina/spotting on the shafts of the counterbores.

Manufactured by 21CM (Alford-Polk), in the USA.

These are very sharp. Trust me, I learned the hard way.

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21st Century 20037 HSS 3/32" Straight Shank Chucking Reamer RHC

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21 Century Manufacturing Counterbore Set 300 Superbore USA Vintage

$300.00

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Century Instrument 610-21A Pneumatic Diaphragm Actuator

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