The Symetrix ARC-EX4e User Interface is used to add more pushbuttons to either an ARC-K1e or ARC-SW4e Modular Remote Control Wall Panel (sold separately). This combination is used to expand remote control capabilities. You can add up to 4 ARC-EX4e to each ARC-K1e and up to 3 ARC-EX4e to each ARC-SW4e. The ARC-EX4e cannot be used as a standalone unit. The ARC-EX4e is furnished with a splash-resistant overlay and mounts into a Decora faceplate (sold separately) alongside its Modular ARC host. The ARC-EX4e shall include 4 momentary buttons with 4 corresponding status LED indicators.