A patented zinc borate product with the combined benefits of higher zinc to boron ratio and water release effect during combustion. This product is suitable for high processing temperatures as its crystalline water is stable up to 415°C. The product's extremely low tendency to absorb surface moisture is suitable for processing conditions sensitive to water release. Typical applications of Firebrake@415 are in nylons, polysulfones, and other polymers requiring high processing temperatures. It is also an excellent smoke suppressant for systems such as flexible PVC.