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STI-1155: Stopper II® with Horn and Spacer (Indoor/Outdoor Rated)

$166.90 $117.99

Stopper II® with Horn and Spacer (Indoor/Outdoor Rated)

This unique and patented cover has helped stop false fire alarms around the world for over 30 years, without restricting legitimate alarms. Ideal for schools, hospitals, nursing homes, stores, hotels and public buildings of almost every kind.

STI-1155 consists of a clear, tamperproof, super tough polycarbonate cover, frame, spacer, gaskets and piezo horn that fits over most manual pull stations. When lifted to gain access to the actual alarm, a piercing 95 or 105 dB warning horn sounds. Immediate attention is drawn to the area and a prankster will either run or be caught. The cover is connected to the frame by a cable. When the cover is lifted, it hangs off of the frame and the horn will sound until the cover is snapped back onto the frame (or for the life of the battery).

This version of the Stopper II is UL Listed for outdoor use.


  • Cover is UV-stabilized.

  • Designed for outdoor use.

  • Three year guarantee against breakage of polycarbonate in normal use (one year on electro mechanical and electronic components).

  • 95 or 105 dB self-contained alarm. Complete with battery.

  • STI-1155 is for surface mount pull stations (flush mount - see STI-1150).

  • The Stopper II design is a registered trade mark of Safety Technology International, Inc.

  • UL Listed to U.S. and Canadian safety standards (for standard and custom labeling).

  • Typical working properties of polycarbonate are -40° to 250°F (-40° to 121°C).

  • Fits virtually all manual pull stations (see Technical Data Sheet for dimensions).

  • Note: End user must verify the alarm and battery function every six months and replace battery annually or as required.