This is a Tillotson AJ-50A carburetor from a Mark era 40CID ThunderBolt outboard, complete as shown. This will fit later models of the Mk55 and several others such as Merc 300, 350 and perhaps the Merc 400 model. There are no cracks welds, stripped threads or other known defects. Ready to overhaul & use.
I have many other Tillotson carburetors in stock. Please inquire.