I use these skulls on the stanchions that we put out front to hold out the front of the house for foot traffic.
They are hollow inside and we just slip them over the wooden stake and then drill a hole in the back of the head to hold them in, and keep them from walking off :)
The cool thing about this skull is that it is made from a cast of a skull that my brother got at Disneyland over 30 years ago.
The face is a bit long and not proportional...but it is a cool skull just the same...and it has a bit of history to it which helps show that our family has always had a taste for the macabre. :D