The Bag is an innovative welded filter bag with a durable non-stitched seam. It has a 180 micron mesh, is resistant to bleach, caustics, and acids, and comes with a convenient resealable locking closure. It is available in a convenient 5" x 9.5" size. It is ideal for all filtration products and has an exceptionally long life. Unlike stitched seams, welded seams are not subject to degradation from exposure to bleach, caustics, acids, or other harsh environmental exposure likely to take place during regeneration of filter media. Caution should be excercised, however, to avoid overfilling or over-packing as welded seams can be forced to separate by excessive pulling forces. Sizes: 13 x 25.5 cm (5” x 9.5”) Comparing Seachem Filter Bags The Bag Dimensions 13 x 25.5 cm (5” x 9.5”) Mesh Size Superfine (180 Micron) Closure Mechanism Plastic Zip Tie Material Polyethylene Seams Welded Resistant to bleach, caustics, and acids Yes Media Compatibility All Seachem Filtration Media Zip Bag Sm Dimensions 32 x 14 cm (12.5” x 5.5”) Mesh Size 25 Mesh Closure Mechanism Zipper Material PVC Seams Stitched Resistant to bleach, caustics, and acids Corrosion-Proof Zipper Media Compatibility All Seachem Filtration Media Zip Bag Md Dimensions 32 x 14 cm (12.5” x 5.5”) Mesh Size 16 Mesh Closure Mechanism Zipper Material PVC Seams Stitched Resistant to bleach, caustics, and acids Corrosion-Proof Zipper Media Compatibility PhosGuard , MatrixCarbon , SeaGel , de nitrate , Renew , Matrix , Zeolite Zip Bag Lg Dimensions 48 x 43 cm (19” x 17”) Mesh Size 8 Mesh Closure Mechanism Zipper Material PVC Seams Stitched Resistant to bleach, caustics, and acids Corrosion-Proof Zipper Media Compatibility Matrix Pond Matrix