A Concrete Brick is a brick
that has a smooth surface and beveled edges with spacers on
This brick comes in matching 4x8, 8x8 and 12x12 sizes which
makes it different from a clay brick (clay bricks only come
in 4x8 and 8x8 sizes). It is primarily
used on a sand base with a thickness of 2 1/4".
Concrete bricks have more of a variety in color.