Hakko Diaphragm Set for Hakko Air Pump (2 pc.) HK60/80 Rebuild KIT POND KOI
(for Hakko 60/80 Air Pump). Hakko Air Pump 60/80 Diaphragm Repair Kit. Note: If your diaphragms are blowing out frequently, you most likely have an excess back pressure problem in your design. Check your air diffusers for clogging.