Compatible with Pentair MasterTemp NA and LP Series pool and spa heater electrical systems. Also compatible with Sta-Rite Max-E-Therm NA and LP Series pool and spa heater electrical systems. Compatible with Mastertemp 400, Mastertemp 300, Mastertemp 250, Mastertemp 200, SR200NA, SR333NA, SR400NA, SR200HD, SR333HD, SR400HD, 460805. No need for any complicated setup. Simply unscrewed the front and back panels, unscrewed the top, yanked all the connectors out and plugged into new board. Also install this membrane pad in minutes for attachment on end of pad makes installation easy. Direct replacement, Impossible to mess up, suitable for DIY. Replacement NA and LP Series Pool/Spa Heater Electrical Systems & 472610Z Switch Membrane Pad Replacement MasterTemp Pool and Spa Heater Electrical System. Begin by removing the old circuit board by shutting down all power and opening the top of the heater tohave access to the old board. Unplug the membrane pad from the board and remove the wire connectors connected to the old board. Unscrew the 4 screws holding the board in place. This will allow you to take the old board completely out. Screw the board back in and plug the membrane pad into the connection that accepts the ribbon cable. Reconnect all of the wire connections and close out your master temp or max e therm heater. A Damage caused by undue ware&tear, misuse, improper installation or operation, neglect, accidents. B Damage caused by natural disaters, flood fire, lightning or pollution. C If item was opened, any parts removed or repaired by any unauthorized person.