Thread & Fitting Size Chart

Thread & Fitting Size Chart



Standard Thread SizeMale Thread Measured O.D.Commonly Used On
BSP 1/2″20.4mmUnder Sink Tap Connections (Mixer/Cistern Taps)
Reactor Filter Housings
BSP 3/4″25.9mmGarden Taps
Laundry Taps (Washing Machine Connections)
NPT 1/8″10.3mmMembrane Filter Housings Quick-Connect Fittings
NPT 1/4″13.7mm10″ RO/DI System Sump-Style Filter Housings
Most Quick-Connect Fittings
NPT 3/8″17.3mmBooster Pump Fittings