Pore size is the number written as µm or um. It is not the diameter of the disc.
The catalog currently includes 0.22, 0.45, 0.8, 1.2, and 2.0. Most packs mention 0.22 or 0.45, or both, because those are the options on that product. A few PTFE listings also offer 0.8, 1.2, or 2.0.
0.22 is a finer pore than 0.45. That is the comparison the number supports. It does not tell you which one your method calls for. If the method says 0.22, filter the shop to 0.22 µm and then read the membrane and the diameter on what remains.
Pore size, membrane, and diameter are separate filters. Choosing a pore and then a membrane keeps both. Choosing two pores means either pore. If the combination comes back empty, that combination is not in the catalog.