Flare UnionMaterial SpecificationC360 (Free Cutting Brass), IS 319, others as per requirement StandardsASTM, JIC-SAE Types of Tube SizesMetric, Imperial Thread StandardsUNF UsesGasoline, Oil, Grease, Water, Air, Vacuum Lines, L.P. & Natural Gas. ApplicationRefrigeration, Air Conditioning, Copper or Brass Tubing, Aluminum, Steel Tubing SizeMetric 4 MM to 25 MM, Imperial 1/8” to 1”