These are our 950HP 3.5" Heavy Duty Carbon Fiber drive shafts for the Eclipse and Talon. This shaft is designed to replace the first 2 shafts of the factory 3-piece system. We were going to try to make a single shaft but due to Critical speed limitations it would need to be 4" in diameter and would not fit under the car and also the operating angles would not allow for a 1-piece shaft to work. The front angle was 2 degrees and the back was 7 degrees (not good), the problem is the rear joint would move more than 2 times as much as the front and cause a very nasty vibration. The AE-7 manual of Automotive engineers doesn't recommend any driveshaft to have more than a 1 degree difference from one operating angle to the other (this would be a 5 degree spread). This shaft comes complete with a conversion plate for the CV end and all hardware to make this a job that can be done in the garage. This Heavy Duty shaft is rated for 950HP.