This part was removed from a 1965 Starcraft Suncruiser 20' w Mercruiser 150 HP GM 4.1L 250ci Inline 6 Dual Carb System w Kiekhaefer Mercruiser 1. 

This is a: Dual Carb Intake Exhaust Manifold  

Stock No: 00G017-JB - 25.9