This model was inspired by the "restraining bolt" used in Star Wars, by Jawas to prevent their droids from wondering off.
Multiple can be stacked, or a magnet (such as http://amzn.com/B000SJ61EC) can be glued into the bottom.
This model is hollow. A solid version is also available.
3.046 w x
3.046 d x
1.199 w x
1.199 d x