Meinl TF-E Tuned Tuning Forks - 136,10HzPLANETARY TUNED TUNING FORKS136. 10 HZ C3# EARTH TF E Handcrafted masterpiece Made in Germany High quality nickel plated steel. The MEINL planetary tuned tuning forks are made in Germany using the calculations of Hans Cousto (The Cosmic Octave) to match the frequencies of the sun, moon, and planets. Each one is tuned to produce the corresponding frequency of the celestial body. These tuning forks have been designed for use in therapeutic applications.