Matrix ZR is a refractory investment developed especially for low expanding porcelains that are used on zircon cores. Although mainly used when working on combination cases, we believe that this is the best refractory for making all porcelain restorations. Because of its low coefficient of thermal expansion, Matrix Zr makes an extremely stable and crack resistant model when compared to other refractory materials. Packaged in a 1 Kg bottle with 8 ounces of mixing liquid. Made in the USA.