Product Description Efficient Filtration: Monotube self-adhesive filter discs are ideal for demanding applications as they both provide air circulation and filter out small objects, providing a healthy and safe mushroom growing process. Excellent Performance: Monotube filter discs are moderately dense to allow fresh air exchange, providing a clean, controlled environment for your mushroom growing and plant cloning needs while maintaining high humidity levels. Perfect Size: Each filter disc is approximately 2.95 inches in diameter and the adhesive is approximately 0.2 inches wide, suitable for covering monotube air holes of 2.5 inches and below. They can perfectly protect the mushroom grower valve. Easy to Install: Simply peel off the protective paper from the monotube filters and attach the filters over the holes in the monotube filter. They are easy to use and remove, saving time and effort. Disk Filter Set: You will get 24 pieces of 2mm thick Mushroom Box Filter Pads for mushroom cultivation, mushroom monotube fruiting chamber, etc., in sufficient quantities for your daily use and replacement. Color: White Material: Cotton Thickness: 2mm Package Contents: 24 * Monotube Self-Adhesive Filter Disks The above package contents only, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3 cm.