Aquarium Equipment -DIY Air Pump Highlights Generic Brand DIY Air Pump Description: Brand new and high quality. Made of EPDM rubber, has good aging resistance. Ultra quiet and long life. Suitable for aquarium air oxygen pump. Specification: Size 1: Inner Diameter: 2.5cm/0.98inch, Outer Diameter: 3.1cm/1.22inch, Height: 1.5cm/0.59inch, Top Small Circle Diameter: About 1.1cm/0.43inch Size 2: Inner Diameter: 2cm / 0.79 inch, Outer Diameter: 3.3cm / 1.3inch, Height: 1.5cm / 0.59 inch, Top Small Circle Diameter: Approx.0.7cm / 0.28inch Package Include: Air Pump Rubber Accessories, 20pcs Note: Since the size above is measured by hand, the size of the actual item might be slightly different from the size shown above. Due to lighting effects, monitor settings etc. There could be a slight difference in the color tone of the pictures and the actual item.