SDC 491S Break Glass Emergency Door Lock with Siren 3V-28V DC, 18mA

Ensure fast, reliable emergency door release and audible alert with the Security Door Controls SDC 491S Break Glass Emergency Door Lock with Siren. Designed for critical access control and lockdown scenarios, this emergency & lockdown button provides immediate notification to security staff and building occupants while integrating seamlessly into existing surveillance and monitoring systems. The SDC 491S operates across a broad 3V–28V DC range and draws just 18mA, delivering dependable performance with minimal power impact. Its integrated siren and break-glass actuator create unmistakable visual and audible cues to accelerate response times during evacuations, medical incidents, or security breaches. Built in the US for commercial-grade durability, the unit is ideal for schools, hospitals, retail sites, government facilities and warehouses where quick, coordinated action is essential. Easy surface-mount installation and compatibility with standard alarm panels make the SDC 491S a practical choice for system installers and security managers looking to improve emergency preparedness. Add the SDC 491S to your access control and monitoring strategy—order now to strengthen facility safety and response.

• Rapid emergency activation with break-glass design and audible siren to alert occupants and security teams immediately
• Wide operating voltage (3V–28V DC) and low current draw (18mA) for easy integration with existing access control and alarm systems
• Durable, US-made construction from Security Door Controls designed for high-traffic commercial and institutional environments
• Clear visual and audible indication simplifies monitoring and reduces response times for lockdown and evacuation procedures
• Simple surface-mount installation and compatibility with surveillance, monitoring and building management systems for fast deployment