Thread size and pitch for AR handgrip screw?

Hello,
I am not at home to check for myself, but am wondering what the thread size and pitch is for the screw that mounts the grip to an AR receiver.

The reason for this is I purchased an unfinished receiver that needs to have the hole tapped. I'm wanting to get the correct tap for the screw that comes in a lower parts kit. Since all finished receivers are already drilled and tapped, I can only assume that the screw size is standard across the industry.

Thanks in advance for your help.
Shovel

Thanks so much for your quick help. That is exactly what I needed so I may get the correct tap.