Specially formulated high yield, high strength mixture of structural lightweight aggregate and cement. Ideal for elevated slabs and walkways, steps, on-grade or suspended slabs, high-rise structural applications and repairs, or wherever weight is an issue. Features 67% more volume than standard concrete, excellent workability, and air-entrained for improved freeze/thaw resistance. Can be mixed in a mechanical concrete mixer or by hand using a wheelbarrow. When used as directed and in accordance with ASTM C 387 Specification, MAXIMIZER Concrete Mix exceeds 4000 psi (pounds per square inch) after 7 days and 5500 psi after 28 days. 40 lb bag.