This fitting will allow the use of aftermarket pressure gauges (1/8 NPT sender) in engines with 1/8 BSP female ports. Many Japanese engines have 1/8 BSP threads for the stock low oil pressure warning light.
Note: Auto Meter labels this adapter as having BSPT (tapered) threads, but it actually has BSPP (parallel) threads.
BSP and NPT nomenclature can be confusing because the nominal sizes refer to the inside diameter of the pipe, not the outside diameter of the threads. If you are not sure what size you need, check in our Threaded Fitting Guide.