Brick symmetry (InstanceAttribute, 4)
From Hi.gher. Space
Brick symmetry is a family of n-dimensional symmetry groups of order 2n, where the existence of any point (x, y, z, ...) in the figure implies the existence of all the points (±x, ±y, ±z, ...). If a figure has brick symmetry, it is said to be a brick. The importance of bricks and brick symmetry stems from the requirement that powertope exponents must be bricks.