STI (STI-14400NR) Universal Stopper Low Profile w/Enc Bkbx

The STI STI-14400NR is a Universal Stopper Low Profile without horn, with enclosed back box and sealed mounting plate — a red, clear polycarbonate protective cover for pull stations, keypads, intercoms, and similar devices in enclosed installations. First, the installer mounts the enclosed back box with its sealed plate to the wall. Then the polycarbonate low-profile cover snaps over the back box on a high-strength continuous hinge. As a result, the device stays operational and visible while gaining additional vandalism, dust, and tamper protection at a reduced wall projection.

What the STI STI-14400NR is built for

Manual pull stations and wall devices in dusty industrial corridors, exterior locations, and high-tamper settings need enclosure protection. However, full-depth Universal Stoppers project further from the wall than some installations allow. Therefore, the STI-14400NR Low Profile variant provides enclosed protection at a reduced projection depth — useful for tight corridors, ADA-critical egress paths, or installations where wall projections are constrained.

Verified STI STI-14400NR specifications

• Family: STI Universal Stopper Low Profile — without horn, enclosed back box, sealed mounting plate
• Cover type: Enclosed back box with sealed mounting plate; low profile, ADA Compliant
• Material: Thick, super-tough, UV-stabilized polycarbonate
• Color: Red enclosed back box; clear polycarbonate cover
• Back box: Enclosed back box (vs. open spacer on the 142xx surface-mount variants)
• Mounting plate: Sealed mounting plate for additional protection
• Conduit knockouts: 3/4 in. tapered thread insert top and bottom (sealed with knockout)
• Mounting: High-strength continuous hinge
• Indoor / outdoor: Rated for indoor and outdoor installation
• UV stabilization: UV-stabilized to keep cover clear over time
• Operating range: Polycarbonate working properties -40° to 250°F (-40° to 121°C)
• Compliance: ADA Compliant — less than 4 in. wall projection
• Listing: UL Listed to U.S. and Canadian safety standards
• Warranty: Three-year guarantee against polycarbonate breakage in normal use

Where STI-14400NR fits in the Universal Stopper Low Profile family

The STI-144xx series is the enclosed-back-box Low Profile Universal Stopper line. Specifically, the NR suffix means No-horn, Red back box; the 142xx siblings (e.g. STI-14200NR) use an open red spacer with surface mount; horn-equipped variants in the line add a piezo tamper alarm. As a result, the STI-14400NR is the enclosed-back-box, no-horn, Low Profile variant.

Low Profile enclosed vs. standard enclosed Universal Stopper

The standard enclosed Universal Stopper (134xx series) projects further from the wall. However, ADA-critical corridors and tight egress paths sometimes require the lowest possible wall projection. Specifically, the Low Profile enclosed cover (144xx series) provides enclosed back-box protection at less than 4 in. wall projection. Furthermore, the 3/4 in. tapered thread inserts at the top and bottom simplify conduit routing for both indoor and outdoor wiring.

Application context

Industrial facilities, manufacturing floors, exterior pull-station locations, and ADA-critical egress paths are typical installations. In addition, the UV-stabilized cover and enclosed configuration support weather-exposed installations. However, this is the no-horn variant — for tamper alarming, specify a horn-equipped Universal Stopper Low Profile enclosed variant.

Need help selecting the right part or verifying compatibility? Our team supports thousands of commercial fire alarm installations every year. Call us at 1-888-557-0558 or email sales@lifesafetycom.com for application guidance, lead-time updates, or volume pricing.