Black and Galvanized Malleable Iron— square head plugs are interchangeable with black cast-iron or steel. NPT
connections. For low-pressure plumbing applications including air, water, natural gas, and steam. Galvanized fittings resist rust
and corrosion,and certified for use in potable water applications. Malleable Iron—Class 300 square head plugs
feature thicker walls to help withstand higher pressures than Class 150 fittings. NPT threads. Suitable for air, water, oil,
natural gas, and steam.