STI STI-1217 Stopper® Dome for Horn/Speaker/Strobe with Open Back Box
Overview
The STI-1217 is a protective dome enclosure designed to shield horn, speaker, and strobe warning appliances from environmental damage and accidental impact. It fits devices with an open back box configuration and is rated NEMA 4, making it suitable for both indoor and outdoor deployments where the base warning appliance carries an outdoor rating. The dome's clear polycarbonate section centers over the strobe lens to minimize light transmission loss — critical when strobes must remain visible across large areas without obstruction.
Compatibility
The STI-1217 is compatible with AMSECO warning appliances, including the AMSECO SL24W-153075 series. It also works with aftermarket colored lens kits designed for that same AMSECO product line. Verify that your existing appliance has an open back box design and matches the dimensional envelope before ordering — the dome is a form-fit accessory with no universal adapters.
Installation Notes
Installation requires six anchor points drilled 3/16 inch diameter, 1 inch deep into the mounting surface. The package includes four Rawl plugs and mounting hardware (four #10 x 1-1/2 inch screws, six washers, and six #8-32 socket head cap screws). An adhesive-backed gasket seals the cover-to-spacer interface. The STI-1217 must be installed per NEC, NFPA 72, and local fire codes. If environmental conditions demand extra protection (salt spray, extreme UV, thermal cycling), order the optional SUB-123 Enviro Kit, which supplies six additional #8-32 x 3/4 inch socket cap screws and conduit sealing gaskets. Center the clear dome section directly over the strobe lens to avoid light loss — misalignment will reduce visible strobe coverage.
What's in the Box
- 1x STI-1217 Stopper Dome (dome + spacer + cover assembly)
- 4x Rawl plugs (for anchor holes)
- 4x #10 x 1-1/2 inch screws
- 6x washers
- 6x #8-32 socket head cap screws
- 1x adhesive-backed gasket (cover-to-spacer seal)
- 1x plastic insert
- 1x mounting template and installation guide
