***** **********Best Quality Guranteed. *****NC mode - (locked while supplied with power), fail safe mode*****Complete mounting hardware for typical installations*****Dual Voltage 12 or 24 VDC (Optional) *****2 Built-in dual-colored status LED and bond sensor to show locking status of each door*****UL listed with the US and Canada. UL Certificate Number 20121130-R27474, it is to certify that representative samples of the product as specified on this certificate were tested according to the current UL requirements