ISTA Stainless Steel Metal Filter Strainer Pipe for Aquarium Fishtank Water Tube Hose (for 16mm pipe) Pore size only 0.6mm, prevent accidently suck in small fishes or shrimps. Suitable for 12mm/16mm inlet pipe. Material : Stainless Steel IF-726 2.95" x 0.95"(L x D); Suitable for 12mm inlet pipe.Centering Hole Diameter 12mm IF-727 2.95" x 0.95" (L x D); Suitable for 16mm inlet pipe. Centering Hole Diameter 16mm Color : Silver Tone