Vibrant Aluminum Transition (2in x 2.5in Tube O.D. x 3in Overall Length)Vibrant Performance aluminum transitions are manufactured from 6061 aluminum and require minimal surface preparation for tig welding. Vibrant Performance aluminum transitions allow for an easy and cost effective way of reducing expanding one tubing size to another and are ideal for fabricators who prefer to not use silicone couplers. They are available a variety of size combinations ranging from 2 to 4.