Just posted a big table of all the different corrective diopters available for all the different Rolleiflex cameras including - TLR's, 6000 series, and Hy6.  Covers waist level magnifiers, 45 and 90 degree prisms.  

Click on the link to see the post... 

Table of Corrective Diopters available for pop up magnifiers in the TLR Waist Level Finder

Rolleiflex TLR  2.8FX   4.0 FW and 4.0 FT    (will also fit 2.8 GX, F, 3.5 F and other models with removable WLF)

Follow the bump to see the table.....