Custom Firescreen 4 Tube Blower KitAdd on a BK4 Blower Kit to get the most heat out of your ZC4 Fireplace Heater. By adding a blower you will get the best efficiency out of your ZC4 heater. The BK4 blower kit includes the blower and front manifold, adjustable 20" flex tube and silicone to seal the manifold to the heater. What's Included 4 Tube 75 CFM Blower Kit Manifold Adjustable Flex Tube Silicone Sealant