The DH924 is a wired 4-inch buzzer/bell great to use in loud environments such as warehouses, workshops etc. If you need an above average sound for a loud environment, this is the one you should choose.
Remote Driveway Bell. Must use Driveway Signal Air Switch 8255330518. Used to power multiple Remote Chimes 8303350520 and Remote Bells 8273350519. Up to 300 feet of Driveway Signal Hose. Must also use Anchor & Hose Plug 819-3350517 with hose.