For intake and cooling systems, 6061 aluminum tubing is the most popular and versatile alloy. Our straight aluminum tubing is sold in the T6 condition, ideal for sawing, machining, sanding, and polishing. All of our bends are initially annealed to the "O" condition, which is necessary for bending. During the bending process, some work hardening in the bend area occurs, and the finished bends are classed as condition "F." The aluminum bends can be polished, but due to the softness of the aluminum, care must be taken not to remove too much material.