If you use pocket filters, you may find different colors. Yes, different colors represent different efficiency.

Usually it`s like following:

>Yellow---F9

Well, do you know how many kinds of filter media there is for pocket filters? Usually there are 3 kinds:

1----Synthetic fiber (with melt-blown layer)

2----Polyester fiber (to make self-supported pocket filters)

3----Glass fiber (has the longest history and the best performance but cannot be incinerable or recycled)

Synthetic fiber is the most popular type. Cause it`s relatively cheap and you can find filter media for all the filter classes(G4-F9). Well for polyester filter, it`s for self-supported pocket filters (available from G4-F7). The pressure drop will be much lower when comparing with soft synthetic fiber. Cause this stiff filter media can support itself. As for the last one glass fiber, its performance is the best. But it`s much more expensive than the others and cannot be incinerable or recycled.

If you want to know more about pocket filters, say standard sizes and pressure drop and so on, feel free to contact us.
Followed please find our advanced semi-automatic production lines for pocket filters: