Aquarium 4 inch Corner Filter Sock Holder with 200 Micron Sock for DIY Fish Tank Sump Filtration Glue In Any Tank Add 4 Inch Sock to Any Aquarium for Better Filtration Comes with 200 Micron 4" Filter Sock Easy to Install to any Aquarium or Acrylic Sump Does not include aquarium Triangle measures 7.25" x 7.25" x 10.25" with 1" bulkhead