For installation requiring additional air flow, such as for use as a central furnace or a multi-story home
- Kit includes one 550 CFM blower with wiring harness
- Doubles the standard air flow
- Easily connects to back of 521FB
- Low power consumption
- Requires #258 dual air filter box
Please Note: Prices, promotions, styles and availability may vary by store and online. While we do our best to provide accurate item availability information, we cannot guarantee in-stock status and availability as item quantities are constantly changing throughout the day. Inventory last updated 5/23/2013 at 5:00am CT. Rebates are an in-store service; therefore online purchases do not qualify towards rebate redemption.