This accessory box contains 12 classic magnetic Magformers triangles which contain free-spinning neodymium magnets safely sealed in every edge. The pack is the perfect stocking filler or birthday present for any child who has an existing Magformers collection - as you simply can never have enough triangles! The pieces are compatible with every Magformers set in existence. Other 12-piece box sets include squares, pentagons, hexagons, diamonds, rectangles, super triangles, isosceles triangles, etc - all the main Magformers building shapes.