With these criteria in mind, we developed our original Magnum tire balancing compound, using microbeads that were round, smooth and durable, plus some additional materials. The roundness and smoothness of the microbeads resulted in the shortest response time to the forces created by the heavy spot in the tire, and the durability of the microbeads ensured that the balancing compound would remain effective throughout its life. (This has meant that all Magnum balancing compounds can be re-used in a retread tire at no additional cost).