a connection is provided whereby a first tube , which may be bent into an elbow , has at least one end flow drilled . during the flow drilling process the first end is shortened , reduced in thickness , and most importantly , the inner diameter is increased to accept a second tube . before connecting the second tube , the first end is preferably tapped with threads which can receive a nut and the nut captures an end of the second tube , preferably entrapping one of at least one bead and a ferrel to provide a connection .