Shure E3, E3C and E3C Pro differences?

[Rgee]

Does anyone know the differences (if any) between the Shure E3, E3C and E3C Pro? I can only find the E3C on Shure's website.

Thanks

RG

[dnd]

AFAIK not such thing as "E3C Pro" and E3 and E3C are identical apart from the colour