Thread Sizes
Checking your BSP threaded fittings

To accurately identify any BSPP or BSPT fitting,
measure from one side of the thread to the other and refer to the chart above.
EG: If the fitting measured 33.249mm across, it is a 1" BSP fitting and you would refer to ot as a 1" BSP fitting.
A 2" fitting would measure 59.614mm across the thread, it is called a 2" BSP fitting.