Here we have a steel weld-on oil, rearend gear lube or fuel filler neck assembly. This 1 1/2" o.d. steel filler neck has a 1 1/4" i.d. and is 1" tall by itself or 1 3/8" with the cap installed. The threaded aluminum cap has a 1 3/4" o.d. with an o-ring seal.
