Taco Comfort Solutions Zone Switching Relay w/ Priority Zoning Circulator 6 Zone. Featuring clearly labeled PC board layouts and advanced features these Air Compressors & Pumps made by Taco Comfort Solutions can be easily customized to work with your home's varying needs. With external indicator lights that provide instant diagnostic feedback the Taco Comfort Solutions Cold Start/Tankless Boiler Zone Switching Relay and Priority Zoning Circulator are a convenient way to identify and troubleshoot any potential issues. With fully enclosed snap-out relays you can easily swap components out to match the demands of your home. This Taco Comfort Solutions 6 Zone ZSR is a universal design that can be expanded to 120 zones (20 Zone Panels). Specifications for Taco Comfort Solutions Zone Switching Relay With Priority Zoning Circulator 6 Zone: Manufacturer: Taco Comfort Solutions Color: Green Power: 120 volts Width: 11.75 in Height: 7.5 in Condition: New Additional Features: 6 Zone Features of Taco Comfort Solutions Zone Switching Relay With Priority Zoning Circulator 6 Zone Number of Zones: 6 Expandable to 120 Zones (20 Zone Panels); Includes the Priority Zoning Circulator External Diagnostic Lights Fully Enclosed Snap-Out Relays Universal Design: Cold Start or Tankless Boiler Package Contents: Taco Comfort Solutions Zone Switching Relay With Priority Zoning Circulator 6 Zone Taco Comfort Solutions SR506-4: Zone Switching Relay w/ Priority Zoning Circulator 6 Zone