This unique Universal Flat Stopper protective cover has helped prevent false fire alarms around the world for almost 40 years, without restricting legitimate operation of devices.

This unique Universal Flat Stopper protective cover has helped prevent false fire alarms around the world for almost 40 years, without restricting legitimate operation of devices.
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STI manufactures high-quality protective covers, cages, alarms, and custom push buttons that safeguard essential life-safety and security devices. Trusted worldwide, STI’s innovative product line helps prevent vandalism, false alarms, and accidental damage, ensuring long-lasting protection and reliable performance for the equipment that protects people and property.

Learn how to easily install the Stopper II® with spacer, the industry’s most trusted protective cover for manual pull stations. For over 40 years, this patented design has helped prevent false fire alarms without restricting legitimate activation. Ideal for schools, hospitals, and public buildings needing reliable alarm protection.

The Steel Web Stopper® high-profile wire guard (STI-9610) protects smoke detectors from vandalism and accidental impact. Constructed of heavy-duty steel wire with a corrosion-resistant coating, this surface-mount design ensures reliability in high-traffic or exposed environments like warehouses, gyms, and commercial buildings.