Use Activator as a surface to firmly strike your tuning fork to “activate” vibration. Activator is tapered so the bottom is wider for stability, when striking from a tabletop or other level surface. Activating tuning forks on the body is not recommended, as injury can occur (bruising, hairline fracture). Use this latex-free, virtually odorless Activator with all tuning forks, weighted and unweighted.