Description / Abstract:
This SAE Aerospace Recommended Practice (ARP) is intended as a
guide toward standard practice for selection of nominal hex widths
for fittings.
Field of Application:
Primarily for fittings which are machined from bar stock and
incorporate a hex wrenching surface. The document applies to union
fittings (both ends the same size). For reducer fittings, use the
hex width for the largest fittings end.