(Ref. #11) The heater cord adapter allows one to plug the current replacement heater element into the pre-1988 Hot Spring control box receptacle. The original control box heater receptacles (standard household style) will not accept the current plug configuration (square) used on the
31255 replacement heater elements.
To use a heater adapter, plug the standard or Nema end into the control box receptacle, then plug the replacement heater element into this heater adapter.