10 Mushroom Spawn Lids with Synthetic Filter Disc, Regular Mouth, 1/2in hole SFD

10 Mushroom Spawn Lids with Synthetic Filter Disc, Regular Mouth, 1/2in hole SFD. These are NEW. Regular mouth polypropylene PP5 white lids. 1/2 inch hole provides perfect gas exchange. The synthetic filter disc is included and installed in the lid. These filters fit neatly within the rim of spawn jars underneath the lid, allowing air exchange but preventing the passage of contaminants. Sterilizable and reusable for life (not for food canning) 99.97% efficient filtration down to .3 microns. For jars with 70 mm diameter openings (regular-mouth canning jars). They work great any mushroom culture in a jar. Good gas exchange helps to make fast colonizing spawn. 10 lids and 10 filters Fast and free shipping Shipped with USPS First Class.