it is heavy. It is 1/4" steel, it has the same holes as camera. It is longer then the camera, so when the fron door shuts you can reach up inside and put lock on it. There is also a piece of steel below camera above lock.
Also it is thicker then camera. this is so I can lock the chain inside box. Basically make a box larger then camera. make a mount for camera to mount to door. Then make sure enough room when shut it can fit locks inside.. Use heavy duty chain. Also use cable, the stuff is damn near impossible to cut.. So unless the drag a cutting torch in they ain't getting it.