This 3/4 inch nylon tap backnut has a BSP thread and therefore has an actual thread diameter of approximately 1 inch
Nylon back nut
IMPORTANT NOTE, MOST PLUMBING PRODUCTS ARE STATED AS BSP IMPERIAL THREAD MEASUREMENT WHICH MEANS THAT ACTUAL DIAMETER OF THE THREAD SIZE IS APPROXIMATELY 1/4 INCH LARGER THAN THAT STATED IN BSP TERMS. FOR EXAMPLE THIS 3/4 INCH BSP THREAD ACTUALLY MEASURES APPROXIMATELY 1 INCH IN DIAMETER
