These are original Schott BG-40 and/or UG-11 filters.
They are made to fit most of 77mm filter rings.
Size of the glass is 74mm in diameter by 2mm thick for BG-40 and 49mm x 2mm thick for UG-11
If you need to see transmission curves for these filters please help yourself and google "Schott UG-11 transmission" or "Schott BG-40 transmission"
Please note that new technician I hired did not polish this batch properly so you will get these filters at incredible discount below cost!
Filters have SOME VERY SLIGHT optical imperfections such as polishing marks.
They will not affect image performance to any significant extent.
Best of all, if you do not like it - return it for full refund. 3 days to check it out!
BUYER PAYS RETURN SHIPPING