Brass Non-Rising Stem Gate Valve 4" Female NPT x 4" Female NPT Male Size_6 Inch The opening starts at the

The opening starts at the top with a 1/2" x 1/2" square and tapers to 9/16" x 9/16" square at the bottom of the opening

See product HS62 for horizontal strainer with back flush cover

The most common size and threads for US fire hydrants is 4 1/2 inch NH / NST

1 1/2" swivel rocker lug female NH / NST by 1 1/2" male NH / NST threaded line pressure gauge

This is the most common plug size in the US

Brass Non-Rising Stem Gate Valve 4" Female NPT x 4" Female NPT Male Size_6 Inch The opening starts at theBrass Non rising stem wedge disc gate valve 4 inch female NPT to 4 inch female NPT. Features a solid wedge disc and integral seat. WARNING: This product contains a chemical known to the State of California to cause birth defects or other reproductive harm. Do not use in connection with drinking water. Wash hands after handling.