The 4 x 4-1/2" Aluminum Nipple is a high-strength, corrosion-resistant pipe fitting designed for secure connections in fluid and air systems. With a 3-1/2-inch nominal diameter and a close-threaded design, it provides a compact, leak-resistant connection between two female-threaded components. Crafted from 6061-T6 aluminum alloy, this fitting offers lightweight durability, excellent thermal conductivity, and resistance to oxidation. Ideal for pneumatic, hydraulic, and industrial plumbing applications.