We have to work with our Teeter F7000 inversion table. When performing physiotherapy exercises, you need to monitor the degree of inclination. Added magnets to the top of the level with a glue gun to allow it to hang down to indicate grades. Maybe stronger magnets are needed, but it works for slow motion. Sturdy and made in the USA. I've dropped it on carpet a few times and nothing has been damaged. I'm so glad I found it.