Punched card available, e.g. "80-column card". A sequence of cards that is input to or output from some step in an application's processing is called a "card deck" or simply "deck". The rectangular, round, or oval bits of paper punched out were called chad ("chads") or "chips" (in IBM usage). Sequential card columns allocated for a specific use, such as names, addresses, multi-digit numbers, etc., are known as a "field". The first card of a group of cards, containing fixed or indicative information for that group, is known as a "master card". Cards that are not master cards are "detail cards". The
Knockout punch sets are available on both imperial and metric sizes. Chassis punches are available in a number of shapes, round being the most common. Other shapes include square, hexagonal, and special shapes for thing such as holes with key tabs and D-sub connectors Special shapes often use bolts that are square or keyed and a separate nut on the punch end to ensure alignment of the punch and die. Knockout punch A knockout punch, also known as a chassis punch, panel punch, Greenlee punch, or a Q-max, is a hand tool used to punch a hole through sheet metal. It is