This Parker brass plug has an internal hexagonal head and male National Pipe Taper (NPT) threads for closing and terminating the end of a pipe or fitting. The plug inserts into female pipes and connects with NPT threads for a tighter seal than straight threads. It has an internal hexagonal head for increased leverage with a wrench during installation and disassembly. This fitting is made of brass, which has excellent thermal conductivity and greater corrosion resistance than stainless steel, and meets standards ANSI B31.1 and B1.20.1 for quality assurance. Parker Hannifin is a leading global manufacturer of motion and control technologies. Founded in 1918 as the Parker Appliance Company in Cleveland, OH, when Arthur L. Parker developed a pneumatic braking system for trucks and buses, Parker Hannifin now provides precision-engineered products for many industries including aerospace, commercial, medical, mobile, and industrial manufacturing. With locations on every continent, and in 48 countries, Parker Hannifin is a multi-billion dollar publicly traded company that offers a variety of solutions for flow control, filtration, and hydraulics, among many others.