The Basican Compass:

The Basican Compass is made of two attached pieces. The triangle piece sets atop the ring piece. Lines on the ring and triangle are cut in. Between ring and triangle, where they do not touch, are three empty spaces. Each of the four arc sections of the ring is a representational color (clockwise from top: black, blue, red, white). The entire triangle piece (including square and circle sections) is of a uniform gray or silver.

In its original size, the outer edge of the ring measures 1 6/16" diameter. Its width is 3/16". Regardless of the size of the ring, these dimensions are to be kept in the same proportion to each other. Also, the triangle is always equilateral and of such a size that all three corners overlap the ring, extending to the outer edge but not beyond it. The top of the square shares a common edge with the top of the triangle. Its bottom corners meet the two downward edges of the triangle. The circle is in the center of the square and measures the same as the width of the ring.