Mercruiser 454 502 mag EFI intake manifold. Excellent condition with ABSOLUTLY no corrosion!!! I have the upper plenum also if needed to purchase seperatly. Please look closely at the picture of the part number in the ad.. I have sold this twice and had to refund it because it was not the right part. It takes the round small O-rings where the injector fits into the manifold. Not The square rubber seals. Came off a 99 502 mag. The fuel pump mounts underneath the motor not on top of the manifold..