 Christmas Crackers, also known as Bond Bones in some regions of Australia are part of Christmas celebrations primarily in the United Kingdom, Ireland and Commonwealth countries such as Australia, Canada, New Zealand and South Africa. The cracker consists of a segmented cardboard tube wrapped in the brightly decorated twist of paper with a price in the central chamber, making it resemble an oversized sweet wrapper. The cracker is pulled apart by two people, each holding an outer chamber, causing the cracker to split unevenly and leaving one person holding the central chamber and price. The split is accompanied by a mild bang or snapping sound produced by the effect of friction on a shock-sensitive, chemically impregnated card strip similar to that used in a cap gun. One chemical used for the friction strip is silver fulminate. The Transportation Security Administration TSA lists English Christmas crackers as an item prohibited from being brought onto an aircraft. Assembled crackers are typically sold in boxes of 3 to 12. These typically have different designs usually with red, green and gold colors. Making crackers from scratch using tissue paper and the tubes from toilet rolls is a common activity for children.