Stainless Steel Mason Spawn Jar Lids - 1/4" Pre-Punched Openings

• We offer these stainless steel mason jar lids by the piece so you can buy exactly what you need.
• Made from stainless steel and will not rust .
• Perfect for mushroom spawn jars and BRF jars.
• Lids have a silicone ring embedded in lid like Bal jars do to keep contaminants out. 
• Each stainless steel lid has 2 pre-punched 1/4" openings for (13mm self healing injection port and gas exchange adhesive  filters which are sold separately). 
• Available in Regular Mouth or Wide Mouth. 
• Note: (Jar bands not included) (Take special care not to bend lids)

Place a 13 mm injection port / butyl rubber stopper into one opening and a self adhesive gas exchange filter over the other opening.  (ports/stoppers and filters sold separately)