The Pentek 144457 Vent Plug Kit comes with the 1/4" Vent Plug and O-Ring.
All #10, #12, and #20 All Natural Pure Polypropylene Housings come with one sump drain plug except those labeled without Plugs.
The 144457 Vent Plugs can be used with All Natural, Pure Poly water filter housings.
The vent plug allows you to vent the housing to drain the cartridge. To use, turn the plug to vent. It is similar to a polypropylene pressure relief. The downside is that there are more threaded fittings and thus more room for contamination. If you are changing filters a lot, the vent plug is nice to have.
Manufacturer: Pentek 144457
Use 144457 Vent Plugs With:
Use with All Natural Pure Polypropylene Housings
Use with #10 Std with Double Cap Plugs 150132 All Natural Housings
Use with #12 222 with Double Cap Plugs without V-bead 150134 All Natural Housings
Use with #20 Std with Double Cap Plugs 150135 All Natural Housings
Use with #20 Ext 222 with Double Cap Plugs without V-bead 150141 All Natural Housings