Package contains two black coarse filter sponges (one with a strainer inside). The strainer inside the one sponge will fit 1/2" uplift tubes and 1/2" tubing. Sponge measures 3"L x 2" diameter (cylinder shape). Fits: Maxi-jet pumps, Maxi-jet power heads, Visi-Jet Protein Skimmers, Visi-Jet pumps, Seaclone protein skimmer, Quicksand biofilters, and will fit most aquariums pumps.