Automatic infrared induction;  adjustable direction (with main rotating bracket); the host has a built-in speaker, and the welcome loudness is 85±5 decibels (the loudest in the visitor chime family); Sound: The first gear is: Ding Dong, Hello, welcome to visit and  the second gear is: alarm sound, (note that the alarm sound is a little small); 3 No. 5 (AA) batteries are powered, energy-saving and durable (this machine does not include batteries);  remote Detection: 0-6 m (applicable tempure-25 degrees)

  Installation and usage:

 1. Push the battery cover on the back of the doorbell in the direction of the Arrow and install three No. 5 batteries (alkaline electricity is recommended

  Pool), cover battery compartment cover.

 2. Turn the doorbell switch to the voice file or alarm file

 3. When a guest enters, the electronic welcome doorbell will make a sound that you have chosen before.

  Matters needing attention:

  Each time the battery is installed, the product needs to carry out "self-inspection" about 15-20s, and then enter the normal working state; sensitivity and volume have been set to standard state, not adjustable; if this product has automatic noise or abnormal phenomenon, please check whether the battery is powered or installed properly (avoid directly facing the light-emitting lamps/sunlight exposure/reflection/direct exposure to the place if the ambient temperature is too high (above 30 degrees) the detector will change from far to near, which is normal.  When the sound of the doorbell becomes weaker, please replace the battery. Try to avoid installing the doorbell in the position directly facing the large air flow variation (such as: air-conditioning outlet, exhaust fan Port, near electrothermal furnace, etc.), don't put it in the sun and rain