STI 3551 Wireless Entry Alert Sensor

Increase situational awareness at entrances and high-traffic access points with the Safety Technology International STI 3551 wireless entry alert sensor. Designed as an additional transmitter and magnet, the STI-3551 extends your door monitoring quickly and without hardwiring—ideal for retail stores, offices, healthcare facilities, and warehouse loading areas. When the transmitter and magnet separate, the sensor sends a wireless signal to the compatible STI-3360 receiver (sold separately) and triggers an audible chime. Choose from ten selectable sounds with the push of a button to match facility needs and reduce nuisance alerts. The compact white housing provides a discreet profile while the wireless connectivity allows installation wherever visibility and quick detection matter most. As part of a broader security and surveillance strategy, the STI-3551 helps teams respond faster to unauthorized entry, improve customer flow management, and strengthen entry-point monitoring. Expand your entry alert coverage with the STI-3551 for reliable, easy-to-deploy door monitoring—add it to your STI-3360 system today.

• Expand door and entry monitoring quickly by adding an extra wireless transmitter and magnet to your existing system
• Immediate audible alerts with 10 selectable chime sounds for clear, customizable notifications
• Wire-free installation for flexible placement on doors, gates, or cabinets to improve security coverage
• Seamless integration with Safety Technology International STI-3360 receiver to scale surveillance and monitoring capabilities
• Low-profile white design blends into commercial and retail environments while enhancing situational awareness