Eshopps’ Micron Bag Holders are easy-to-install filter bag holder for any sump filtration system. The Micron Bag Holder enhances mechanical filtration, which helps reduce the amount of ammonia-producing organic matter in your aquarium. It also helps prevent larger objects such as sand, crabs, and snails from damaging pump motors, as well as unsightly aquarium debris. Micron bag & Bulkhead included. PF-XL (XLarge) holds 2 Rectangular bags