JIC 37 Degree Flare & UNO (O-Ring Boss)
JIC – Joint Industry Council – SAE J514, ISO 8434-2
UN – Unified National – SAE J1926, ISO 11926-2
JIC & UNO (O Ring Boss) thread forms are the same (ASME B1.1). Method of sealing differs
JIC : Male has a 37° Seat. This seat is the sealing face (face that stops the leaks). When screwed into a JIC Female the 37° Male seat will seal up against the 37° seat of the female.
For joining tube together or to adapt a tube to another fitting – A JIC Tube nut + Sleave can be used. The tube will need flaring to 37°, the end result is a female JIC end.
UNO (O-Ring Boss) : Although the thread is the same as JIC, the sealing method is different. All UNO male’s will have an O-Ring, this O-ring is the seal, it will sit in the female port spot face. For Elbows and Tee’s there is an added backup washer and lock nut on the fittings to allow for different orientation.