Another poster said:
"The bolt is M8 x 1.25mm pitch. The hole depth is 23mm. "
However, the first two metrics are okay, but that last dimension of 23mm is not long enough.
I tried it and was not comfortable with the length as it seemed it could fall.
I would recommend a longer bolt.
I purchased this mount
"OmniMount Full Motion Wall Mount for 55"-82" TVs" for $49 on black friday deal.
Lots of bolt options are included in the mount kit and they worked fine.
I have used Omni Mounts for years for my IT customers and they are easy to install.