6F22 9V Polarized Battery Case

This battery holder is safer then usual commercial battery holder because it is polarized, you cannot insert battery with wrong polarity (yes, if you use violence, you can).
It is parametric, so you can easily customize it, if you have a spring of different diameter you can change its value into the OpenScad code.
If you like, you can use this project to add a battery pocket into the case of your electronic project.