Hope you can see they are 1" outside the thread. They don't even exceed 3/4" of the inside diameter of the hole. I don't know if this is a packaging error, a deliberate attempt to confuse, or I don't know anything about industry sizing. Home Depot sold the same package and it was 3/4". Since my box had different sized punch holes, I was able to use them, but be aware that if you only have a 3/4" punch hole, they will NOT fit. .
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