A system built for the aftermarket.. With 7 relays, the BP7 has 32 different setups and can power a spa with 1-4 pumps, including Microsilk systems. Can also replace any Balboa BP System* while using the existing topside that is already installed on the spa. Will replace any Balboa VS or EL System* when you match it with any TP or SpaTouch topside panel. Will replace any Balboa or other brandâ€™s non-low flow system* when you match it with any TP or SpaTouch topside panel. This system can only be used at 220v.