What is the object Kathy Jordan is knocked out with?

My VHS copy of this film is very dark so a lot of things are hard to see well. We see a glimpse of this thing as Donny grabs it and conks her on the head with it. It looks like a sort of a metal version of a DNA helix with something shaped like an ashtray on top.

Does anyone know exactly what this thing was? A machine part of some sort? Was it something that was in the house before the filming and just ended up getting used for the scene? If this was a historic house, as another thread on this board claims, a lot of antiques had to have been inside it.

yakko