OD 4 5 6 8 10 12 14 16 18 20 22 25 28 32 34 40 42 Imperial thread 1/8" 1/4" 3/8" 1/2" 3/4" 1" 1 1/4" 1 1/2" Metric thread M10?1 M12?1.5 M14?1.5 M16?1.5 M18?1.5 M22?1.5 M27?2 M33?2 M42?2 M50?2 Model sample:Tube OD is ?12,terminal thread is R3/8" and max working pressure is 25Mpa ,the ream joint with taper thread is marked :Q/ZB204-77R1" ?28