Aqua-Flo Rigid Pond Filter Media, 12.5" x 72" (6 Feet) 1" Thick (nominal) Uncompressed. May Vary Between .75" and 1" Due to Shipping 50 Micron Nominal 100% Polyester Random Strand Non-Woven Filter Media Larger Open Fiber Design Allows for Maximum Flow Rate. Media is BI-DIRECTIONAL Works Well in All Environments/Completely Non-Toxic. Fresh Water/ Salt Water, Washable Proudly Made in the USA by an American company