Note:

1) The extra remote control and alarm need to pair,

2) One remote control could control many alarms,

3) One alarm could be controlled by at most 8 remote control.

Detailed instruction:

How to pair remote control with alarm?

1) Press and hold the learn button(It is also door bell button) don't release the button,

2) Next, load the battery into the alarm, you could hear the sound "bi", please also don't release the learn button as the step 1).

Within 10s, you could hear sound "bi" again, which means the alarm is in learn mode,

3) Then release the learn button and press any one of other three button once, you can hear sound "bi bi", which means the pair is successful.