I took the screw off the bottom of my Gibson LP and went to Guitar Center to compare it with the diameter of the Loxx screw. The Loxx screw was a hair smaller and had a different thread on it. I played around with the locking mechanizm, it was hard to pull off and when the top piece is not centered with screw in piece (like it would be if you were wearing your guitar) it is very very difficult to make it release, so I got them. They were actually 3 dollars cheaper at the store than online, a Guitar Center first for me.
When I got home and screwed them in it was a tight fit, no need for toothpicks or glue. I put the locks on the strap. This may be hard to do if you love your strap and don't want to make the holes a little bigger.(Don't lose the tool they come with or removing the clasps may be challenging.)
I put it all together, put the guitar on and went through some tests to see if it would snag off or what I thought it would take to make the lock fail.
This system passed with what I would be willing to do while wearing what I consider to be a very expensive guitar- strap locks or not.
BUT always consider the law of physics that says whatever can go wrong will eventually go wrong....
or something like that
and they look good too