The Fzone Glass Lily Pipe Set are ultra-clear borosilicate glass made to blend in with your aquarium. Provide the perfect habitat for your livestock with the Fzone Glass Lily Pipe Set. Package include skimmer lily Inflow pipe, outflow pipe, 10-13 glass adapter and spring brush. 10mm to 13mm glass adapter allows user connect with 12mm hose ID 9mm hose ID.