they are real moon rocks used in the 2009 NYC FRC with the real regolith used to play on. it was cut into a cup shape and connected using self tapping screws. they are hidden using the tracking color fabric glued on. the whole thing is placed on 7" X 7" 3/8 lexan base. its truly a peice of history. we had to clean the regolith with neutral cleaner and a lil elbow grease. these suckas are heavy.