Howe's UJ-3212 joins a 7/8" smooth (Sm) shaft to a 3/4"-36 spline shaft, so you can bridge two different shaft ends without an adapter. Howe lists it as the Charlynn U-joint, for connecting to a Charlynn valve shaft.
- End 1: 7/8" smooth (Sm) (code 32)
- End 2: 3/4"-36 spline (code 12)
Howe lists this joint family in a long list of spline combinations, so if your ends are different, check the other UJ part numbers.
Howe Performance part number UJ-3212.