Increase the air flow by adding a second blower to the back of your DAKA furnace. Move more warm air through long duct runs or up to a second or third level of your home. Kit includes: One 550-CFM Blower with motor, wiring hardware and detailed installation manual also included. Compatible with DAKA furnace models: 511, 511D, 512, 512D, 521, 521FB, 621, & 622.