This is an Aquarium Protein Skimmer Model "Visi-Jet-Ps 100" in Good Condition. It is designed to work with tanks up to 70 gal. and includes: Prefilter, Submersible pump, Flow control knob, Air valve filter, Foam concertation chamber, Foam collection cap, Contact chamber, and Directional output. The skimmer has a slim profile for in tank use and easy access to the collection cup for cleaning. You can regulate the amount of water flow from 20gal/hour to 90 gal/hour in conjunction and the amount of exterior air flow intake. It includes instruction sheet. Pick up only from Cobble Hill.