Microppose 18mm 0.3 Micron Self-Adhesive Lid Filter Stickers for Jar Lids & Tissue Culture (50-Pack)
Microppose 18mm 0.3 Micron Self-Adhesive Lid Filter Stickers for Jar Lids & Tissue Culture (50-Pack) is backordered and will ship as soon as it is back in stock.
Couldn't load pickup availability
Description
Description
Turn any jar lid or culture container into a breathable, contamination-proof workspace in seconds. The Microppose 18mm 0.3 Micron Self-Adhesive Lid Filter Stickers peel and stick directly over a drilled hole in metal or plastic lids, letting your culture breathe while blocking airborne spores and bacteria.
Backed by industrial-strength 3M adhesive, these filters stay put through handling, autoclaving, and long incubation runs — no peeling, no falling off. Each sheet gives you 50 filters, making them the fastest, most economical way to build your own sterile lids for injections and transfers. The compact 18mm size is perfect for grain spawn jars, liquid culture jars, and small tissue culture vessels.
Why Growers Choose These Filters
- True 0.3 Micron Filtration – Stops contaminant spores and bacteria while allowing clean, consistent gas exchange.
- Won't Fall Off – Industrial 3M adhesive holds through autoclaving, humidity, and months of incubation.
- Lightning-Fast Application – Peel and stick in seconds; no cutting, taping, or polyfill stuffing.
- Breathes Better – A proprietary micron layer resists moisture saturation for faster, cleaner colonization.
How to Apply
- Drill or punch a hole in your jar lid or tissue culture lid (a 1/4" hole works well for 18mm; add a second hole for extra airflow).
- Peel a filter from the sheet and press it firmly over the opening, centering it so the adhesive fully seals around the hole.
- Pair with a self-healing injection port for a complete DIY sterile lid ready for inoculation and transfers.
Key Features
- 0.3 micron filtration efficiency – blocks spores and bacteria, allows clean airflow
- Strong 3M adhesive backing – stays put even after autoclaving
- Hydrophobic & oleophobic – resists moisture saturation and oil
- Fully autoclavable – high-temperature resistant for repeated sterilization
- Made from 100% recycled material
- 50 filters per sheet – 18mm round
Common Uses
- Grain spawn jars and liquid culture jars
- Agar work and spore-to-liquid culture
- Plant tissue culture vessels and containers
- DIY sterile lids for injections and transfers
Unlike the re-purposed filters sold everywhere else, these use a unique proprietary micron layer that does not break down from steam, resists moisture saturation, and breathes far better than cheaper alternatives — giving you faster, cleaner colonization every time.
Frequently Asked Questions
What size hole should I drill for these filters?
Drill or punch a hole smaller than the filter so the 3M adhesive fully seals around the edge. For the 18mm size, a 1/4" hole works well, and you can add a second small hole for extra gas exchange on grain jars.
Can these be autoclaved or pressure cooked?
Yes. They are fully autoclavable and high-temperature resistant. The 3M adhesive and proprietary micron layer hold up to repeated steam sterilization without peeling or breaking down.
What can I use them for?
Grain spawn jars, liquid culture, agar work, and plant tissue culture vessels — anywhere you need sterile gas exchange. Pair them with a self-healing injection port to build a complete DIY sterile lid for inoculation and transfers.
How is 0.3 micron different from cheaper filter discs?
The 0.3 micron layer blocks bacteria and mold spores while still breathing well. Unlike re-purposed filters, this proprietary layer resists moisture saturation and does not degrade from steam, so you get more reliable, faster colonization.
Should I get the 18mm or the 28mm?
The 18mm (50 per sheet) is ideal for standard grain spawn jars, liquid culture jars, and small tissue culture containers. Choose the 28mm (21 per sheet) if you want more filter surface area for larger lids, wide-mouth jars, or tubs where extra gas exchange helps.
Complete Your Sterile Lid
Pair these filters with a self-healing injection port to build a reusable DIY sterile lid you can inoculate again and again without contamination.
Shop Injection Ports & Lid FiltersLet customers speak for us
i saw germination in my jar within 2-4 days!! I ordered a 3 pack and i injected 3 different strains and they are all colonizing and germinating very rapidly i see ne difference in rate of germination for genetics they are all moving about the same speed im happy with my purchase!
100% RELIABLE EVERY TIME I LOVE YOU MIDWEST THANL YOU TEAM
Reliable and I know what I am getting. Pretty quick colonization.
I got the grow bag instead of jars this time because I am not interested in the steps of the jars.
Been there done that.
I am not an expert🤓 but now I have enough knowledge and experience to call myself an apprentice.
The thrill of the process is gone. Just give me the dam mushrooms.
I am hurry up and waiting😉.
Seems to be working is all I have to say at this point day 7. The green is reflection not mold.
All I knew was I wanted to grow some mushies for me and the boys, I did a bunch of research on companies and you guys have been around the longest and have the best reviews for these types and I was not disappointed. Took exactly 8 weeks to harvest my first 4 ounces and more on the way! Thanks so much for all the awesome guides and videos! Made it so easy!
It's a great monotub kit. I recommend throwing the horse booster, used the whole bag to 4 small quick grain jars and the 7.5 mix. I learned how to do a pf tek with these guys 10 years ago when you still got the sticky light for the lid and the monotub was a blue tub with polyfill. These monotub kits have come a very long way since then. Substrate has always been clean and performed better than what I try to recreate with a pressure cooker.
10cc liquid culture and follow the instructions mgk gives you hard to mess up.
So far , I only have a little bit on agar , and am only beginning to study this mycelium. Super excited to try to put it to use in this Aspen tree.
Everything is looking real good so far
If your ever in need of replacing your hepa filter on your bonsai flowhood these are an exact match to whichever size you have. Worth noting that a filter will actually work a lot longer than is recommended due to physics but if your externals get dirty or damaged it’s worth replacing.
Shipping was lightning fast
I like everything about this setup. The time of ownership is too short to discuss fruiting mushrooms but the incubating mycelium seem to be doing well for now under the recommended temps. The one thing that would make this setup better would be the inclusion of an electronic controlled hygrometer to run the vaporizer.
Unit was just giving 0 on everything except air Temp and Humidity. Called customer and they are taking care of. Happy with customer service.
I think these are the best co2 boost bags on the market especially the price. More bang for your buck. My buds have been alot bigger, and alot more dense, stacking like a roll of silver coins! And alot more of a yield too! I will always use these co2 bags in every grow, they are definitely worth it! Unless you like fox tailed loose and airy buds!
These pellets work very well. Especially if you do no-low heat drying. Also helped,e save some that got soggy. I put a pinch of the pellets in the jar, and they dried up overnight.
