Bluestar International manufactures Bulk Head Union Tube Fitting. Bluestar International is an ISO 9001: 2000 and ISO 14001:2004 certified company offering a wide range of instrumentation tube fittings, valve fittings, flanges and piping products. The Bulk Head Union Tube Fitting is available in different tube diameter size ranging from 1/8 inch to 1 inch and comes in various specifications for application in instrumentation and process control system tubing, double ferrule compression tube fittings and tubing lines.