Gecko TSC-2 Topside Control - old design for early 2000's spa.  Mechanical type thermostat control dial with pneumatic air button for pump.  One indicator light for Heat.  One use would have been Infinity Spirit spa from 1998-2000.  Other uses and spas as well.  If your control looks like this, it might be the control for you.  PLEASE remember there are no returns on electronic items.  All products are new.  If you have an issue, please contact us prior to initiating a return.