The Chakra Set is a set of 7 tuning Forks that can be used with the chakra system.This Tuning Fork is made in Aluminium metal and anodized with GOLD coating. Free Rubber Mallet with this Tuning Fork Set. These forks are NOT based on a musical scale. They work more on the cosmic multi-dimensions of our chakras, our not noticeable bodies or subtle parts. They also work on pathways as well as other gateways of energy. The planetary cycle of the solar System is used to arrive at accurate formulae on which these tuning forks have been created. This links them to our cosmic multi-dimensional selves. Our this self is eternal, very not noticeable and approachable through layers, ladders, gateways and manifold levels of energy. These Tuning forks prepare pathways to a Cosmic Universal understanding of Life and our Souls infinite relationship to it. In comparison, It is unlike the Harmonic Spectrum Set, which is tuned to the Pythagorean Scale (also known as the Just Scale) and is more in touch with the physical plane of existence and works at a more physical level. The physical plane is more concentrated, crystallized in definite form, cognitive and revolves around the 5 human senses and various parts of our physical body like the tissues, fluids, bones, organs, etc. A Swiss mathematician and musicologist Hans Cousto had developed them. These 7 Tuning forks are based on: 1st Root/Muladhara (also Earth Day) 194.18 Hz 2nd Sacral/Svadhisthana (also Synodic Moon) 210.42 Hz 3rd Solar Plexus/Manipura (also Sun) 126.22 Hz 4th Heart/Anahata(also Earth Year)(also OM Fork) 136.10 Hz 5th Throat/Vishuddha (also Mercury) 141.27 Hz 6th Third Eye/Ajna (also Venus) 221.23 Hz 7th Crown/Sahasrara(also Platonic Year) 172.06 Hz All our Tuning Forks are made from special grade Aluminium alloy and frequency is guaranteed to tuned to an accuracy of +/- 0.25% which is very good for healing.