JARDLI Lily Pipe Outflow Spin for Plants Aquarium Has a loop-shape outflow section. Spin outflow pipe creates a circling flow of water inside its loop section, and slows the speed of water flow. 13mm diameter fit for the hose of 12/16mm. Easy to remove, when it time to clean your tank. Can be installed on the aquarium without using a suction cup. Package included: 1x Lily pipe spin outflow, 2x Suction cups.