Product Description: China Zinc Plated DIN934 Hex/Hexanal Nut is used in conjunction with bolts and screws to connect fastening machine parts.The type 1 hexagon nut is the most widely used, and the Grade C nut is used for the machine, equipment or structure which is rough on the surface and is not high in accuracy. Grade A and Grade B nut are used for the surface to be smooth and require high precision for machines, equipment or structures.The thickness of the type 2 hexagon nut is thicker, and it is often used in the occasion of needing to be disassembled. The Zinc Plated hex nut will typically last twice as long as the standard hex nut, less likely to rust over time.