The ZD Stereotactic System has a design that permits safe and simple use. It has a small ceramic headring that is MR-compatible, allowing imaging to be done even in the latest MRI scanners. Zamorano und Duchovny states that the ZD system is based on the principle called center-of-arc. The access it gives to all intracranial areas is almost unrestricted. It also provides total freedom of choice when it comes to the trepanation point. The ZD system easily stands out because it is easy and safe to use. The single-point attachment technique allows the mounting of the aiming unit to 1 of the 4 positions on the headring. This gives access to all areas of the cranium coming from any direction. Checking the target point simulator provides safety and can be done anytime.