Simplex, now part of Johnson Controls, is one of the most widely installed fire alarm brands in North America. Simplex systems are found in hospitals, universities, airports, high rises and industrial plants, and they are maintained for decades rather than replaced. That long service life is exactly why the parts are hard to find, and it is what this collection is aimed at.
With well over a thousand Simplex line items in stock, we cover:
- Simplex smoke detectors and sensors - photoelectric, heat, combination photoelectric and heat, and carbon monoxide sensors, plus replacement cartridges
- Sensor bases, including standard, sounder and relay bases
- Duct detectors, duct housings and duct covers
- Addressable modules - individual addressable modules, zone adapter modules, relay modules and NAC extenders
- Single and double action pull stations, break rods and station keys
- Horns, strobes, horn strobes and speaker strobes, wall and ceiling mount
- Device covers, cover plates and trim in red and white
Much of what we hold is discontinued or superseded Simplex stock kept specifically for existing installations. If a part is not listed, send the number through our quote page.

Simplex
Simplex 4090-9107 IDNet Fiber Optic Transmitter, Class A Style 6, Multimode
Sale price$502.30
Regular price$602.76
Not in stock - available on backorder - lead time on request
Simplex
Simplex 4098-5251 MX 850 Addressable Photoelectric Smoke and Heat Multi-Sensor with Isolator
Sale price$39.90
Regular price$47.88
In Stock
Simplex
Simplex 4098-5252 MX 850 Series Addressable Photoelectric Smoke Sensor with Isolator
Sale price$38.65
Regular price$46.38
In Stock
Simplex
Simplex 4100-1246 Flex Amplifier Class A Adapter (Speaker NAC)
Sale price$109.25
Regular price$131.10
In Stock
Simplex
Simplex 4100-1273 Telephone NAC Class A Adapter for 4100-1270/1272
Sale price$60.55
Regular price$72.66
In Stock
Simplex
Simplex 4100-1280 Red LED Module
Sale price$298.30
Regular price$357.96
Not in stock - available on backorder - lead time on request
Simplex
Simplex 4100-1291 (742-727) Remote Unit Interface
Sale price$278.70
Regular price$334.44
In Stock
Simplex
Simplex 4100-9920 4100ES Three Bay Retrofit Kit, Red with Glass Door, for 2120 and 4100 Deep Backbox
Sale price$1,453.00
Regular price$1,743.60
In Stock
Simplex
Simplex 4190-9050 Remote AMZ Package with Cover
Sale price$267.25
Regular price$320.70
In Stock
Simplex
Simplex 4901-9859 SmartSync Two-Wire Non-Addressable Mini-Horn, White
Sale price$42.75
Regular price$51.30
In Stock
Simplex
Simplex 4903-9356 TrueAlert Non-Addressable Speaker Strobe
Sale price$103.45
Regular price$124.14
Contact Us for Alternatives
Simplex
Simplex 4906-9136 Chime/Strobe Ceiling White
Sale price$139.40
Regular price$167.28
Contact Us for Alternatives
Simplex
Simplex 565-653 Duct PCA Circuit Board Assembly
Sale price$60.75
Regular price$72.90
In Stock
Simplex
Simplex 4905-9817 Cover Plate, Surface Mount, Beige
Sale price$25.55
Regular price$30.66
Not in stock - available on backorder - lead time on request
Simplex
Simplex 49AVC-CRFIRE Cover, Red, "FIRE"
Sale price$14.55
Regular price$17.46
Not in stock - available on backorder - lead time on request
Simplex
Simplex 562-805 Switch Circuit Board LED
Sale price$225.70
Regular price$270.84
Only 5 units left
Simplex
Simplex 562-799 Motherboard, Style B with Suppression
Sale price$184.45
Regular price$221.34
In Stock
Simplex
Simplex 636-064 100 W Audio Amplifier Assembly, 70 V, 4100 Series
Sale price$1,126.90
Regular price$1,352.28
Only 1 unit left





