OverviewSpecsFAQsGalleriesResourcesReviews Product Description Easy to Finish Concrete Countertop Mix The Z Counter-Pack conversion kit is a multi-component admixture kit for converting a standard 60 lb bag of concrete mix into a high-performance, easy-to-finish concrete countertop mix. Each Z Counter-Pack kit is a precisely measured recipe for a consistent blend of cement and other proprietary materials which will produce significantly higher strength and reduced set times over the standard mix. Ideal for use with either pre-cast or cast-in-place applications. One box mixed with a 60lb standard bag of concrete mix will yield 3.75 sq ft in our forms (1-5/8″ thick). In commercial forms, it will yield approx. 2.25 sq ft.