This is the Protuner Nissan SR20DET to 350Z Gearbox adapter kit it is the best Gearbox solution for high power SR20 engines. Our plate makes the strong and refined 6 speed 350Z gearbox bolt up to the SR20 engine. The 350Z gearbox is superior to the SR20 RB25 and 300zx in both strength and shift quality even at high rpm. Read more about SR20det to 350z gearbox adapter