In this category, it is listed whether the mount is attached to the optical device with rings or via rail. In the red dot sight adapters section, it is written which red dot sight the adapter is made for.
If the mount is attached to the optical device with rings, the ring diameter is listed:
25.4 mm/1 inch (in most cases interchangeable with 26 mm)
30 mm
34 mm
35 mm
36 mm
40 mm
If the mount is attached to the optical device with rail, the rail type is listed:
LM rail
Zeiss ZM/VM rail
Swarovski SR rail
S&B Convex rail
Picatinny rail
Pulsar Apex, Trail, Digisight
Dedal NV
Fortuna General
In the red dot sight adapters section, it is written which red dot sight the adapter is for:
Docter sight mounts
Aimpoint Micro mounts
Zeiss compact
Trijicon MRO
Shield sights
C-more
...