The MyAlert wireless Smart Phone transmitter easily connects your smartphone to the MyAlert remote receiver for amplification, sight and even vibration to alert you to calls, text messages, email and all the functions you designate on your phone. Setup is a breeze, simply install 2 AAA batteries and follow the three step easy-pair setup. Your smart phone's ring or vibration is detected and a signal is sent to the receivers. MyAlert receivers will alert you with your choice of light sound, bright flashing LED's or a powerful bed shaker. The SP10T has three levels of adjustable sensitivity (high, medium, low) so you can dial in the level that works best for you.