2-1/2" NST (NH) Female x 3/4" GHT Male Brass Fire Hydrant Adapter with Pin Lug Fire Hydrant Adapter Brass Fire Equipment for Garden Hose Great for hooking a hose to a hydrant.Hydrant adapter connects the hose to a hydrant with a pin lug for quick disconnectSide 1-Male 3/4" Garden Hose Thread (GHT) for connecting to a hoseSide 2-Female 2-1/2" National Standard Thread (NST) for connecting to the hydrant Male side – 3/4” garden hose thread (GHT) Male side – 3/4” garden hose thread (GHT). The male will only connect to a female 3/4” GHT Female side – 2-1/2” NH / NST thread Female side – 2-1/2” NH / NST thread. The female will only connect to a male 2-1/2” NH / NST IDM of 2.5"" NST / NH adapter is 2.9"" Inside diameter of 2.5"" NST / NH adapter conforms to NFPA 1963 Standard for Fire Hose Connections 2014 Edition" "Great for hooking a hose to a hydrant. hydrant adapter connects the hose to a hydrant with a pin lug for quick disconnectSide 1 - Male 3/4"" Garden Hose Thread (GHT) for connecting to a hoseSide 2 - Female 2-1/2"" National Standard Thread (NST) for connecting to the hydrant NH / NST: The most common thread type in use by fire departments today is NST or National Standard Thread. NST also goes by the initials NH or National Hose. It can even be referred to as NHT or National Hose Thread. But NST or NH is more common these days. NH = NST.NPSH: National Pipe Straight Hose (NPSH) or Iron Pipe Thread (IPT) has the same threads per inch (TPI) as National Pipe Tapered (NPT) but the thread does not taper. NPSH is a straight thread and seals by a gasket in the female coupling which allows for a swivel, just like NH / NST, which make both ideal for hose couplings. Warning - It will NOT thread into a female NPT pipe. For example, a male NPSH coupling will NOT thread into a female metal or pvc pipe. Hose To Hydrant Adapter: The brass garden hose to hydrant adapter fit small opening on New York fire hydrants.Perfect fire hydrant to 3/4 hose includes garden hose, pipes and other fittings.The fire hydrant hose adapter likes a hook which connects a hose to a fire hydrant adapter together. The fire hydrant adapter fittings connects to fire hydrant to hose adapter provide high volumn water output for watering garden and orchard, washing car,firefighters firefighting applications Specification: Material: Brass Package includes: 1 x Fire Equipment Brass Hydrant to Garden Hose Adapter Features: 1.Size:Male side -3/4" garden hose thread (GHT) for connecting to a hose and Female side - 2-1/2" NH / NST for connecting to the hydrant.2.Function:This fire hydrant adapter can be used to connect pipes, hoses or fittings of different types.3.Quick Connect/Disconnect:The pin plug can realize quick connect and disconnect, easy to use. Hose To Hydrant Adapter: The brass garden hose to hydrant adapter fit small opening on New York fire hydrants.Perfect fire hydrant to 3/4 hose includes garden hose, pipes and other fittings.The fire hydrant hose adapter likes a hook which connects a hose to a fire hydrant adapter together. Warm Note: 1.Small products, please keep away from children to prevent swallowing2.Manual measurement, please allow slight errors on size.3.The colors may exist slight difference due.