The product is 1 pairs, a total of (single) 2 filter cottons.
Effective filtering ? 99.95%.Excellent filtering effect, you deserve it.
The product cannot produce oxygen, please do not use it when the oxygen concentration is lower than 19.5%.
Cannot be used alone,used with 6000,7000,FF-4 Filter Retainer.
Compatible with 5p71.Please confirm this is the model you need before placing an order.