The ProBangle is made from pure metal and are harmonically energized / charged to help improve and assist the flow of energy in your body as well as helping protect it from electronic stress and electromagnetic interference Because of the pure metal element from which the bangle is made the ProBangle is RECHARGEABLE and will last up to 3 years dependant on interference The ProBangle absorb the resonance properties of the harmonics that are used to energize it The ProBangle is harmonically energized / charged to help improve the flow of energy in your body