Nut conforming to DIN 439. Also known as a half nut, thin nut, or jam/lock nut. Typically fitted with a spanner or ratchet with socket, often used in pairs or in conjunction with a hexagon full nut in a locking arrangement. A popular nut type, and used for decades on all types of assembly throughout the world. Fine Pitch and Left Hand Thread variants are also available immediately below this item.