MJ Threads are used in Aeronautical Industry - for Metric system.
Specification
• ISO 5855 - Part I, II, III - 1999, OR ANSI B 1.21 M - 1997 & ANSI B1.22 M - 1985.
Manufacturing Range
Thread Plug Gauges 1.6 mm - 300 mm
Thread Ring Gauges : 2 mm - 300 mm.