Wing Nuts
Wing Nuts, Type A Style, is a nut with wings that is made from stamped sheet metal and has a moderate height and a larger bearing surface than forged wing nuts.
Wing Nuts, Type D Style, also is a nut with wings but is forged and is generally smaller in height with a smaller bearing surface than stamped wing nuts.
They are both used when a part is frequently assembled and disassembled at a place where torque greater than that achieved with finger pressure is not needed.