Khadi or hand-spun cloth is the only material allowed to be used for the flag, and flying a flag made of any other material is punishable by law with imprisonment up to three years, besides a fine. Raw materials for khadi are restricted to cotton, silk and wool. There are two kinds of khadi used: The first is the khadi-bunting which makes up the body of the flag, and the second is the khadi-duck, which is a beige-coloured cloth that holds the flag to the pole. The khadi-duck is an unconventional type of weave that meshes three threads into a weave, compared to the two threads used in conventional weaving. This type of weaving is extremely rare, and there are fewer than twenty weavers in India professing this skill. The guidelines also state that there should be exactly 150 threads per square centimetre, four threads per stitch, and one square foot should weigh exactly .