Phresh – Pre-Filter SocksPhresh – Pre-Filter Socks Suitable for Phresh Filters and Phresh In-Line Filters. Phresh Pre-Filter Socks use a proprietary fibre count/density dacron fabric that breathes up to 50% better than off the shelf dacron. Phresh Pre-Filter Socks have been tested to filter down to 50 microns which is twice as much as other off shelf dacron. Protect your carbon filter and make sure it flows the maximum air to ensure a cool, well ventilated room.
