Features: brand new and high quality Glass transparency give superb appearance to your aquarium. Make an elegant curve line in your aquarium. Spin outflow pipe creates a circling flow of water inside its loop section, and slows the speed of water flow. 10mm inner diameter fits for 30-50cm/11.for 81"-19.69" fish for tank, 13mm inner diameter fits for 60-90cm/23.62"-35.43" fish for tank, 17mm fits for 100-180cm/39.37"-70.87" fish for tank. for Eheim, Tetra and other filters. They can be installed on the aquarium for tank without using suction cups. Package includes 1 piece lily pipe inflow, 1 piece lily pipe spin outflow. Specifications: Material: Glass Color: Transparent Size: S/for M/L S-Approx.Pipe Diameter Approx.1.0cm/0.39in, Height Approx.14cm/5.51in M-Approx.Pipe Diameter Approx.1.3cm/0.51in, Height Approx.15cm/5.90in L-Approx.Pipe Diameter Approx.1.7cm/0.66in, Height Approx.17.5cm/6.88in Weight: Approx.250g Package Includes: 1x Lily Pipe Inflow 1x Lily Pipe Spin Outflow note: 1.Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!