RAM MOUNTS Ball Thread M8 RAM-B-367U

Typically, RAM MOUNTS have the distinguishable 1-inch ball on a base plate, which you then attach to something else. Here, they take a different tack and give you just the ball. It comes pre-drilled (M8 threaded) and with a 55, 60 and 65mm bolt, ready for you to attach it just about anywhere.

So, in theory, the only limitation is that the available screw thread is also M8. Suppose you use a smaller size, keep in mind that the load-bearing capacity is no longer guaranteed.