If you have a 1968 GT 350 with a 4spd or an automatic that had smog, now might be a good time to grab these tubes. They are very nice reproductions copied from a NOS tube. They are concours correct and replace the often missing or damaged thermactor tubes. Even if you don't put them on the car for daily driving, they are good to have. Hey, if you score an NOS set, these will still have good value. Steve, the guy who builds them, says dont cry, when they are gone....now's the time! They also fit Fairlanes and Torinos...and yes the 1968 tubes are unique!!