u2032 includes a pawl 41 u2032 at a distal end 42 u2032 thereof for adjustable engagement with teeth 38 u2032 upon relative movement of opposed ends 34 u2032 and 36 u2032 teeth 38 u2032 are engaged by pawl 41 u2032 to provide adjustable interlocking therebetween this allows the diameter of the circular stent 28 u2032 to be adjustably expanded in incremental fashion to set the diameter thereof at discrete increments now with reference to fig4 an additional embodiment of a stent is shown stent 28 u2033 is a wire stent employing telescoping ends the wire 30 u2033 is formed in a circular configuration and includes a first end 34 u2033 that is positioned in general axial alignment with a second opposed end 36 u2033 a distal portion 34 a u2033 of first end 34 u2033 telescopes into an elongate open ended channel 44 u2033 formed at opposed end 36 u2033 the diameter of the stent 28 u2033 is contracted and expanded by movement of first end 34 u2033 into and out of open ended channel 44 u2033 the various embodiments of each of the stents 28 described herein are preferably manufactured out of a bio compatible metal most preferably the bio compatible metal is stainless steel platinum gold nitinol tantalum and alloys thereof one or more such stents 28 may be disposed between tubes 12 and 22 for example in one embodiment a single stent 28 is disposed about one end of tube 12 in an alternative embodiment of the invention two stents 28 are disposed about each end of tube 12 in yet another embodiment of the invention several stents 28.