Manifold stud with shoulder 2-5/8" long. This style with the shoulder was used by Ford from 1924 until August of 1926 when they switch to a bolt with a domed head, part# 3066D
These studs attach manifold clamps to engine block, They thread into the block and the shoulder acts as a stop. The nut holds the clamp part# 3065 in place to secure the manifold to engine.
The stud nut is included.