Simplex 4090-9802 4-Inch Fire Alarm Surface Cover

Simplex 4090-9802 is a 4-inch Zam surface cover plate for mounting a Simplex IDNet or MAPNET II module in a 4" square back box, also cataloged as 0742313. This Zam trim plate provides a clean exterior for surface‑mounted fire alarm installations in commercial settings and is designed to be used with 4" surface-mounted back boxes to preserve module indicators through a built‑in light pipe, with orientation specified to ensure the LED remains visible on the installed module. It serves as the finish component in IDNet/MAPNET II configurations, commonly chosen in retrofit or new construction where surface mounting is preferred over semi‑flush or flush options. By pairing the cover with the appropriate mounting bracket and back box, technicians achieve a professional, durable appearance while maintaining access to the module’s indicators and keeping the installation compliant with standard Simplex mounting practices.