It can be polyester BUT it is a thin fabric material NOT suitable for aquarium backing. I would return it but it's not worth my time.
πͺ¨ 5-Pound Bag of Spectrastone Special Blue Gravel for Freshwater Aquariums
10 Review
π Spectrastone Shallow Creek Regular: Enhance your Freshwater Aquariums with a 5-Pound Bag
9 Review
Faucet for kitchen (sink) Blanco Fontas II (granite) pearl
16 Review
π AquaticHI 27-Inch Aquarium Tongs - 100% Reef Safe - Multi-Purpose for Fresh & Saltwater Fish Tanks - Clip Plants, Spot Feed Fish & Coral - Keep Hands Dry
9 Review
π Enhance Aquarium Maintenance with hygger Carbon Fiber 6 in 1 Cleaning Tool Kit β Algae Scraper, Scrubber Pad, Sponge, and Telescopic Handle for Optimal Fish Tank Cleaning in Saltwater and Freshwater Environments
5 Review
FISH PROS Fine Mesh Handle
3 Review
π Tetra No More Algae Tablets 8 Count: Effective Algae Control for Aquariums
8 Review
π 1-Count Container of Glass Aquarium API Algae Scraper
4 Review