RBS carries a complete line of PSI roots blower snout assm's. All snouts are made from billet alum. then anodized black and use a twelve bolt pattern to attach themselves to the front cover. They use a billet heat treated drive shaft that uses the industry standard 2.782" bolt circle with six 3/8-24 bolt holes.
Blower snout coupler is sold separate under part #1400-0055.