The ZBFB Bottom Fire Bolt eliminates the need for the bottom automatic flush bolt and dust proof strike. The ZBFB is installed horizontally in the inactive door, with a mating hole in the edge of the active door. It is usually fitted within 102-152mm of the bottom of the door. When subjected to 230°F (110°C) the ZBFB projects a spring-loaded bolt, locking the leaves together. This product contains no intumescent.
Fire rated for 3 hours on metal doors and 20 minutes on timber doors (US only).
The ZBFB can be purchased separately or as part of a kit with the 842, 942 and 862/962 single automatic flush bolt supplied for the top of the door and the ZBFB supplied for the bottom of the door.