Wing Nuts

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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.