Originally Posted By: DSparks
I asked the seller what the micron rating and efficiency is on these filters and they responded with "B10=X"....whats that mean?
Originally Posted By: sayjac
....As for efficiency if that is a concern, that is generally vague, unauthoritative or unknown. Then again, if that or coo is not a priority as it isn't for many, all of the above should function satisfactorily for a standard ~5-6k mi. oci....
...As I said. But considering the target market, mainly jobbers I assume, knowing exact efficiency not a priority for many/most of them either. And, at .71 cents a filter I wouldn't have has too great an expectation if it being otherwise, and it doesn't put it out of the ordinary with other jobber filters.
Otoh, if one were paying a premium price like ~$15 for a filter and it had no published standard ISO 4548 -12 test efficiency, then I would consider it a scam, and certainly hiding something. But that's not the case here.