TidalFit Spa Pack – MVS504SZ was used in select TidalFit Swim Spas 2012-2013.
This is circuit board, heater and plastic box all in one.
MVS504SZ 33-0612-08
To convert this board to a 3 pump system you need the Daughter Board.
Pro Tip: Now would be a good time to replace the heater gaskets also.