Simplex 4905-9903 Red Fire Alarm Adapter Plate

The Simplex 4905-9903 is a commercial fire alarm adapter plate designed for compatible Simplex notification appliances. Specifically, it provides a secure retrofit mounting solution for approved horn, strobe, and audible/visual devices installed on the Simplex 2975-9145 mounting box. This product is intended exclusively for commercial fire alarm installations and is not consumer electrical equipment, communications equipment, surveillance equipment, or recording devices.

Manufactured from durable steel with a red finish, the 4905-9903 simplifies retrofit projects by allowing newer compatible notification appliances to mount securely on existing back boxes. In addition, its low-profile design helps maintain a clean and professional appearance after installation.

Product Functions

The Simplex 4905-9903 supports commercial fire alarm installations by providing:

• Retrofit mounting for compatible notification appliances
• Secure installation on the Simplex 2975-9145 mounting box
• Support for compatible horn and strobe devices
• Durable steel construction
• Professional finished appearance
• Simplified replacement and upgrade projects

Electrical & System Information

The 4905-9903 is a passive mounting accessory and does not require operating voltage. Instead, it provides a mechanical mounting interface between compatible notification appliances and the Simplex 2975-9145 back box.

Furthermore, the adapter plate supports retrofit installations where replacing the existing mounting box is unnecessary. Always verify compatibility before installation.

Features

Retrofit Installation

The adapter plate allows compatible notification appliances to mount onto existing Simplex 2975-9145 back boxes. As a result, retrofit projects become faster and more cost-effective.

Heavy-Duty Steel Construction

Constructed from durable steel, the plate provides dependable mechanical support for commercial fire alarm notification appliances.

Low-Profile Design

The slim profile maintains a clean finished appearance while minimizing additional projection from the wall.

Professional Red Finish

The red finish matches commercial fire alarm equipment and provides consistent appearance throughout the installation.

Reliable Mounting Solution

Designed specifically for compatible Simplex equipment, the adapter plate helps ensure secure appliance installation during new construction and retrofit applications.

Mounting & Design

The Simplex 4905-9903 features a rugged steel construction with precision mounting holes for approved notification appliances. Furthermore, it installs directly onto the Simplex 2975-9145 mounting box, allowing straightforward installation without modifying the existing enclosure.

Its compact design makes it well suited for commercial retrofit applications where maintaining existing infrastructure reduces installation time and labor costs.

Protection & Applications

The 4905-9903 is designed exclusively for commercial fire alarm notification systems.

Typical applications include:

• Retrofit notification appliance installations
• Horn mounting
• Strobe mounting
• Audible/Visual notification devices
• Commercial fire alarm systems
• Building renovation projects

Always install the adapter plate according to local building codes, fire codes, and the manufacturer’s installation instructions.

Compatibility

The Simplex 4905-9903 is designed for use with the Simplex 2975-9145 mounting box and compatible Simplex notification appliances requiring this retrofit adapter.

Before purchasing or installing this product, verify compatibility with the intended notification appliance and project requirements.

Technical Specifications

Manufacturer: Simplex

Model: 4905-9903

Product Type: Commercial Fire Alarm Adapter Plate

Color: Red

Material: Steel

Application: Retrofit Mounting Plate

Compatible Mounting Box: Simplex 2975-9145

Compatible Devices: Select Simplex Horns, Strobes, and Audible/Visual Notification Appliances

Installation: Indoor Commercial Fire Alarm Systems

Mounting Orientation: Vertical or Horizontal (application dependent)

Dimensions: 8.31 × 5.75 × 0.06 in (211 × 146 × 1.5 mm)

Construction: Heavy-Duty Steel

Always verify technical specifications using the manufacturer’s official documentation before installation.

Applications

The Simplex 4905-9903 is commonly used in compatible commercial fire alarm systems serving:

• Office Buildings
• Schools
• Universities
• Hospitals
• Healthcare Facilities
• Hotels
• Government Buildings
• Retail Stores
• Warehouses
• Industrial Facilities
• Commercial Buildings

Before installation, verify compliance with local codes, project specifications, and manufacturer recommendations to ensure proper system operation.

4905-9903