• Home
  • STI Wireless Entry Alert Sensor

STI Wireless Entry Alert Sensor

SKU: STI3551

Usually ships in 3-5 days.

Pay in 4 interest-free payments. Learn More.


WARNING: Cancer and Reproductive Harm – www.P65Warnings.ca.gov


Receive Alerts When Your Door is Opened

Monitor a door and receive an alert when it opens using the STI Wireless Entry Alert Sensor. Part of the STI Wireless Chime Series, the sensor wirelessly communicates with an STI Wireless Receiver (sold separately) to notify you when triggered. The sensor consists of two parts — the main battery-powered sensor and a magnet — which install on the door frame and the door itself. When the door opens and the two parts are separated, an alert is triggered.

  • Monitors a door to alert you when the door opens
  • Works with any STI Wireless Receiver
  • Includes double-sided tape for easy mounting


  • Entry Alert Sensor
  • Battery, AAA
  • Double-Sided Tape

Note: Requires an STI Wireless Receiver to alert you. This sensor is not self-supervised for low battery; check battery every 6 months to ensure reliable operation.

We Protect The Things That Protect You®

Safety Technology International (STI) is a family owned and operated business that began over 35 years ago with Jack Taylor's invention of the Stopper Pull Station Protector. STI now markets more than 1,000 products throughout the world that help prevent false fire alarms, theft, and vandalism of the devices that protect us all.


  • Manufacturer Part #: STI-3551
  • Frequency: 433 MHz
  • Wireless Range: Up to 500 feet (line of sight)
  • Power Source: One "AAA" battery (supplied)
  • Battery Life: approx. 1 year
  • Approvals: UL, cUL, FCC, IC
  • Warranty: 1-Year Limited