What Drive Shaft, Strange or Mancini Aluminum 1350

Dustedu2 said
Why does Denny's and Strange say 30 spline 727 slip yoke and Mancini's says 29 spline slip yoke? are there 2 different ones for the 727?

The yoke just has one spline missing to relieve potential pressure. It's the same style yoke except for that.