Fittings are available in two sequence: the DIN 2353 L (mild) and also the DIN 2353 S (hefty) classes. Each series has its individual tube sizes and thread Proportions as revealed within the desk beneath: The Joint Industries Council (JIC), sought to distinct the air by standardizing the requirements on http://arthurlnnlj.thezenweb.com/How-jic-fittings-can-Save-You-Time-Stress-and-Money--30255877