Superspeed Design Change ?? (Nerd Alert)

Just noticed something i never noticed before, i have a few superspeeds in my collection, on two of them a Z2 (1954) and B4 (1956) the first part of knurled handle above the TTO Knob is twice the size of the other superspeeds that i have....? the earliest Superspeed with the normal size part is a C1 (1957)

looks like after the first three years of superspeed going into production (1954-1956) the design was changed, wonder if it makes them worth more to a collector...



All the other details on the Razor are the same:

Interesting

Can I just add the design changes later on on the black handled ones:

First ones:



Later ones:


Baseplate changed in 1978, but the knurling only changed a bit later on.



Max

Yeah - I'd noticed a slight difference between FT super speeds. I also noticed that the curvature of the heads is slightly different. Can't remember the dates - will have to go and check a bit later