I was planning to use it for groove cutting for M7 blind hole but it could not be used
On 2016-10-22 00:04:47
I bought an upper tap for the blind hole of M7 and M6, but neither was able to be used because it was a protruding center. Somewhat dissatisfied are the descriptions that "protruding center depending on size" is only described, concrete size is not written. I regret to return it.