Our new 18 piece pack contains uniquely rounded triangular pieces, that when joined side by side created a perfect half circle on a base built from two trapeziums.The shape can be expanded to a full sphere or ball shape if desired. The shapes allow endless build options with the dome pieces being able to be used individually or together.Our NEW18 piece set includes: 6 red curved triangles 6 green curved triangles 2 orange trapezium 2 blue trapezium 2 yellow trapezium The tiles are robust with a raised lip on the edge to protect the face from scratching.Stronger food grade ABS plastic, riveted and plastic welded with an internal logo to create a flat and more scratch resistant tile.