1、open & close with 3-8 digit code.2、3 indicator lights indicate open,low battery and warning.3、Use the knob to open and close with a solenoid system.4、supply the override key for emergency use.5、change the code easily with reset button.6、include the protective floor carpet.7、run on 4X1.5V AA batteries.8、2 bolts with 13.5mm.9、Pre-drilled holes at the button and back.