A solid concrete masonry unit, rectangular in shape, usually not larger than 4 in. by 4 in. by 12 in. (10 cm by 10 cm by 30 cm); made from portland cement and suitable aggregates; may include other materials.
A solid concrete masonry unit, rectangular in shape, usually not larger than 4 in. by 4 in. by 12 in. (10 cm by 10 cm by 30 cm); made from portland cement and suitable aggregates; may include other materials.