This Velocity Boiler Works Hex Nut is a robust and durable component designed for heavy-duty applications. The nut features a 5/8 inch - 11 thread size, which is a standard measurement indicating the diameter and threads per inch. It belongs to Grade 9 (GR-9), signifying its high strength and resistance to wear, making it suitable for use in demanding environments. The term "HEAVY" refers to the nut's heavy hexagonal shape, which provides a larger wrenching area for better load distribution and ease of installation.