This refers to a specific type of plumbing fitting commonly used to change the direction of a pipe run at a 45-degree angle. The “1/8 NPT” indicates the fitting’s size and thread type; 1/8 inch National Pipe Taper (NPT) is a standard thread specification for creating a tight seal in plumbing applications. These fittings are often stocked by large home improvement retailers.
Such components are essential for creating efficient and leak-proof plumbing systems in residential and commercial buildings. The 45-degree angle offers a less abrupt directional change compared to a 90-degree elbow, potentially reducing flow restriction and pressure loss. Historically, fittings like these have been integral to plumbing infrastructure, evolving from simple cast iron designs to more modern materials like brass and plastic to improve corrosion resistance and ease of installation.