Phresh 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. Hydroponic - Pre Filters protect your carbon filter and make sure it flows the maximum air to ensure a cool, well ventilated room.