I occasionally get questions about the different Om tuners available. There are two common Om tuning forks, the 136.1 hz which is sometimes called the Mid Om and the Low Om whose frequency is 68.05 hz. It is called the Low Om because it is octavized by 1/2 (136.2 / 2 = 68.05). Click here to learn more about octavization.
If you feel a connection to Earth frequencies then this is certainly a fork you should have. If you are just starting out then get the 136.1 hz / Mid Om first. This fork creates a very soothing, meditative tone that most everyone likes. The Low Om is an octave lower and has a deeper resonance. It is still very good and I definitely recommend it for those working with Earth frequencies.
The only physical difference is that the Low Om is a longer tuning fork. Remember, the 136.1 hz is not better or worse than the 68.05 hz, just different. Select the one that feels right to you. If you are not certain, choose the mid om 136.1hz or contact us for assistance.