When you want the best performance mid-pipe, choose Cobalt. Designed by our in-house Engineering and R&D team with consulting from our California neighbor, Magnaflow. Full stainless steel 2.5" pipes and welded-in 48-state catalytic converter, this bolts to factory or Cobalt headers and mufflers. Factory location O2 connection. Great for supercharged, turbo, or naturally-aspirated Miatas. When you have Moss, Cobalt and Magnaflow working together, you get the best product. Not CA or NY legal. Not CARB legal.