This Cap Will Only Connect To A 2.5 NH / NST Fire Hydrant
Material - Iron
Supplied with Chain and Ring
Color - Red
Description
Heavy duty 2.5 inch replacement iron fire hydrant cap with NH / NST threads including chain. Pentagonal in shape.
The most common size and threads for US fire hydrants is 2 1/2" NH / NST.
2 1/2" Male Fire Hydrant
Inside diameter of a male adapter - 2 1/2" inches
Outside diameter of a male NH / NST adapter - 3.06 inches (7.5 Threads per inch)
Outside diameter a male NPSH or NPT adapter - 2.84 inches (8 Threads per inch)