Our balancing media consists of two parts. The first one is durametal, a hardened lead allow similiar to lead shot but 10 times harder. This is the primary balancing media because a solid cannot change shape or form under centrifugal force. It remains exactly where needed under high speed. The second part, the dampening fluid is proprietary synthetic oil, designed to operate in the most extreme environments. The rings are about 1/3 full of this fluid. Its function is to lubricate, dampen vibration and help balance. However, a liquid alone would merely flatten out under centrifugal force at high speed and be forced back around the ring to and undesirable position. That's why we use the benefits of both a solid and liquid.