Thread ring gauge LR

M - ISO metric thread MF - ISO metric fine thread G - Whitworth pipe thread BSW - British Standard Whitworth thread BSF - British Standard Whitworth fine thread R - Tapered Whitworth pipe thread Pg - Steel conduit thread MF-EL - Electrical conduit thread UNC - Unified national coarse thread UNF - Unified national fine thread UNEF - Unified national extra fine thread UN/UNS - Unified national thread, Unified national special thread UNJC - UNJC Unified national coarse thread UNJF - UNJF Unified national fine thread NPT - American Standard taper pipe thread NPTF - American Standard taper pipe thread Tr - ISO metric trapezoidal thread GO/NOT GO thread ring gauge with step limit