Federal Signal’s Model 121S is a compact, rotating warning light designed for in-plant use. It features a parabolic reflector which rotates around an incandescent lamp, providing 60 flashes per minute in all directions. 

Federal Signal’s 121S comes ready to mount on a 1/2-inch NPT pipe or surface mount. Optional brackets simplify installation on walls or in corners (see pages 128-131). The enclosure is also rated Type 4X for a water-tight and dust-tight seal. 

The lamp projects an intense, fixed beam onto a parabolic reflector which rotates 360°, producing 60 flashes per minute. The 121 features a twist and lock dome which allows for fast and easy access to inspect and change the lamp. 

This light is particularly useful as a signaling or warning device in high ambient noise areas where it can supplement audible signaling devices. It is also effective alerting for hazardous conditions or dangerous areas. 

Federal Signal’s Vitalite is an economical rotating warning light for emergency warning or status indication in noisy areas.


Mount 1/2" Pipe
Voltage 120VAC 50/60Hz
Operating Current 0.36 Amps
Lamp Life 3,000 Hours
Light Source/Lamp Style Incandescent
Flash Rate/Minute 60
Peak Candela 2100
Operating Temperature Minimum -31 °F
Operating Temperature Minimum 150 °F
Enclosure Rating Type 4X
Ingress Protection (IP) IP66
Dome Colors Amber
Net Weight 2 lb
Shipping Weight 2.10 lb
Height 6.260 in
Diameter 5.130 in

Ordering Information

Model Types
Model Description UPC
121S-120A Rotating light, 120VAC, surface or pipe mount, amber 782979284901
121S-120B Rotating light, 120VAC, surface or pipe mount, blue 782979284802
121S-120C Rotating light, 120VAC, surface or pipe mount, clear 782979285007
121S-120G Rotating light, 120VAC, surface or pipe mount, green 782979386308
121S-120R Rotating light, 120VAC, surface or pipe mount, red 782979284604
Product # Description UPC
LCMB2 Mounting bracket, corner 782979253709
LWMB2 Mounting kit, wall mount 782979253808
Replacement Parts
Description Part Number UPC
Dome, amber, 121 light K8444357A-02 782979122920
Dome, blue, 121 light K8444357A-01 782979122913
Dome, clear, 121 light K8444357A 782979122906
Dome, green, 121 light K8444357A-04 782979122944
Dome, red, 121 light K8444357A-03 782979122937
Incandescent lamp, 40W, 120V, Series C K8107251A 782979125525
Lamp, incandescent, 120V, 25W K8107181A 782979118190