Including: Water Pressure Regulators, John Guest Fittings, Brass BSP ( British Standard Pipe) Fittings and more.
Most espresso machine fittings are BSP, which are also referred to as "gas" fittings. They come in Imperial sizes (1/8, 1/4, 3/8...), not metric. The thread pitch is different from American NPT fittings, and therefore are not interchangeable. BSP fittings come in two versions: BSPP (parallel / straight) and BSPT (tapered). In almost all cases, only BSPP threads are used in espresso machines. The following general guidelines will help you size your fittings.