The Rhino II is the best designed 4" bottom drain for use in Gunnite, Shotcrete or Concrete but will also work excellent in 45 mil EPDM liner ponds. The Rhino II 4" bottom drain has an air diffuser dome for added airation. Your air is pumped  in a separate 1/2" line next to the 4" bottom drain line. Remember that aerated bottom drains like the Koitoilet I and Rhino II require an air pump like the Medo Air Pump.

Quality materials and superior construction differentiates the Rhino II 4 inch bottom drain over Spindrifter 4" bottom drains. A few of the problems associated with the Spindrifter 4" bottom Drain have been alleviated in the Rhino II 4" bottom drain design including;

• Thicker flanges and liner attachment ring that will not flex or crack
• All attachments are machine fitted for extra strength with no need for gap filling
• All joints are hand welded resulting in more strength than the speed welds used on the Spindrifter and other 4" bottom drains.
• 3" height over the horizontal discharge port for more concrete over the horizontal discharge port (the Spindrifter 4" bottom drain requires a collar to increase the height over the drain)
• Direct pipe connection into the air bladder (the Spindrifter bottom drain requires you to snake an air line through the bottom drain)
• Rhino II 4" bottom drain with air dome contain an air check valve to prevent water entering the air line