Question:
What does the suffix /26/64/66/95 in the SKU mean?

Answer:
The horn wave guide coverage patterns for each model [rotatable waveguide for vertical or horizontal orientation] are:
/26 =120H x 60V degrees
/64 = 60H x 40V degrees
/66 = 60H x 60V degrees
/95 = 90H x 50V degrees