🎈【Package includes】32 pieces micropore of filter stickers with a diameter of 20mm and 15 pieces micropore of filter stickers with a diameter of 84mm (waterproof film) can allow air circulation, which are mushroom growing supplies. The Membrane Filter Sticker can make your mushrooms grow better. 🎈【High filter rate】These viscous filters of micropore have a filtration rate of 99.97% and can filter 0.25μm. 🎈【Easy to use】Before using the viscous filters of micropore , you need to clean and dry the surface. The Membrane Filter Sticker can be applied under the holes of the wide mouth can cover, allowing for fresh air exchange while preventing unnecessary pollutants from entering. 🎈【Widely applicable】These viscous filters of micropore have excellent heat resistance and pressure resistance, and are widely used by some mushroom suppliers and home growers. The Membrane Filter stickers are also suitable for wide-mouth canned tank covers, steam sterilizers, high-pressure sterilizers, etc. 🎈【Worry-fr*ee after-sales service】All Our Mushroom Growing Supplies are strictly inspected before delivery. Please don't hesitate to contact us if you have any questions. Our all-weather after-sa~les service and one-year fr~ee replacement service. If our mycology supplies can't satisfy you, please don't return them, con~tact us and we will provide you with the best solution.