Product # MP-25R Filter: .2 micron Thickness: 65 micron Type of Plastic: Polypropylene 14" x 4" x 4" approximately 2.5lb of substrate 1000 bags Please note: Mushroom filter bags do not qualify for free shipping due to weight and size. For orders larger than 1 case (1000 bags) email us at sales@farwestfungi.com