What are Sway-A-Way/Nismo torsion bars?

They are conventional 4340 torsion bars made by Sway-A-Way for Nissan Motorsports. The bars are 26.5 mm in diameter and are larger than OEM torsion bars, which are 24.5 mm in diameter. They are approximately 30% stiffer than stock. Comes as a set of two bars, generally painted with a white epoxy.