Countersink Holes

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A countersink is a conical hole cut into a manufactured object, or the cutter used to cut such a hole. A common usage is to allow the head of a countersink bolt or screw, when placed in the hole, to sit flush with or below the surface of the surrounding material.

 
Countersink Holes Countersink Holes
 
 PCB Countersink Holes
 
 PCB Countersink Holes
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