4 in 1 multi-function: 4 modes to meet your various choices: normal alarm, constant alarm, delay (turn off the alarm) and doorbell, just press the button to select the function you need without any complicated settings. This touch sensor kit can quickly detect the status of your doors and windows. Requires 2 AAA batteries (not included). Freezer Door Alarm with Delay and Widely Available: Upgraded version has 3/15/30/60 second delay to choose from. Magnetic Trigger Door Alarm Sensor Protects Home Through Window Entry Doors, Suitable For Safes, Cabinets, Freezers, Refrigerators, Sliding Pool Doors, Shops, Offices, Apartments, Hotels, etc. 108dB loud enough to keep your home safe: Door and window alarms help to deter intruders and thieves effectively with a loud 108dB alarm, and the open chime will also notify you if companions/elderly children/pets arrive or leave unexpectedly. It keeps your kids from sneaking around. It is the perfect wireless security magnetic alarm for child safety, burglar, home, garage, mailbox and business security. The Home/Window Contact Sensor Alarm comes with a self-adhesive pad, so no tools are required, just stick the door alarm sensor to the door or window. It can also be used as a door plug alarm, swimming pool door alarm, garage door alarm or sliding door alarm. Low-power design provides practical long-term protection. They can work for more than 2 years. Installation precautions: Be sure to turn off the alarm and the magnetic strip, and the installation distance between them should not exceed 2cm. The 2 parts must be aligned by their alignment arrows. Packing: 1 piece