Master Spa topside control panel Designed to Control Swim Spa Propulsion System. 2 button blank panel (No Overlay) is Rectangular w/ Rounded Sides and has LCD Display. You must purchase overlay for complete replacement. Measures 10.25" x 3.8". This Keypad is Compatible with the following series/system(s) - Master Spa Proprietary Controls by Balboa. Also Found in the following spa models - Master Spa Models H2x Swim Spas (2011) RX, Signature, Momentum 50, Momentum 80, Impact, Force, Michael Phelps Swim Spas (2012-2013) Signature S, Signature, Momentum 50, Momentum 80, Impact, Force.