Just an update on the collets discussed in this thread.
The Burnerd MC collets all have 8 fins, which looks to be what was used in the pic of the Salvaged Star Destroyer Capacitor Bearing.
Burnerd have a similar sized collet, the EC range which only has 6 fins, which looks to have been used in some posts here (also in a still from the film shown earlier).
Which shows that several, slightly different props were used in the film.
All EC & MC collets are the same size, but the ranges of collets are distinguished by their "Bore" diameters, IE:-MC range goes from MC2 (1/16"-3/16")-MC13 (1 3/8"-1 1/2").
The EC range is similar. Pic below shows both types together to show fin spacing.
The EC collet in my pic has a spot welded end stop.
Hope this clarifies a few things.