3 ms·
If you don't test how do you know the filter works?
by apexalpha 3y ago
If you don't test how do you know the filter works?
- smt88 3y agoThe filters are independently tested (officially by certification companies and unofficially by product reviewers). One of the brands, Berke, actually resisted independent testing and was removed from a lot of reviewers' lists of recommendations.