"Federal Signal Viper S2" knockoff

I saw one of these things are a regional training event, and I thought it was pretty bright. So, I wandered down into the bowels of ebay and bought the cheapest one I could find. On the listing, it never mentioned "Federal Signal". The description was "16 LED warning light". I think one of the pictures in the listing showed a FedSig label. I figured they just used a picture from FedSig's website. I paid a whopping $18.

After a couple of weeks shipping from China, the following is what I got.

Packaging: LOL yeah, right.

In the box: 1 warning light, 1 flashback shield, 1 mounting bracket, 3 suction cups.
[Broken External Image]:http://[URL=http://s1148.photobucke... firefighting/20170413_151615_zpsogwozbax.jpg

Close up of LEDs: Solder joints look good enough. The diodes don't look that great. A lot of surface imperfections on the lenses.

I have it running on a lab power supply right now. I'll turn it off for the long weekend. But when I get back to work next week, I'll let it run for a full day and see how it does.

Initial impressions are that it is friggin' bright! Video to come soon.
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Yeah, I saw a similar picture on an Amazon review. No question it probably uses the cheapest material possible. But, if I know that going in, I can adjust to improve its survival (thermal shielding, good ventilation, etc). I will do a full deconstruction after today's 8hr run test.

I turned it on around 6:30am. I'll get some thermal imaging readings a bit later to check on PCB resistance and chassis heat dissipation.
I tried really hard to get some quantitative data on how "bright" it is. We have a test hood at work that can give me brightness in Candela, but the light doesn't have a steady-burn mode...so I couldn't get super accurate readings.

In a double-double flash, the sensor recorded a median value of 24.2 Candela. In a "ludicrous flash" (it's like a really bright flicker), the sensor was consistently recording higher than 60 Candela. In my world, that's not very bright on paper. But I don't think our test rig is well suited to this type of product. This Viper knockoff has reflectors, and optics, and it's line-of-sight brightness will be much higher than it's overall brightness.

Typically, I see manufacturers advertise the power of the diodes in "Watts"...which is admittedly a bit deceiving because each diode is really only using a fraction of a watt each. If someone can clue me in to an actual industry standard of warning light brightness...I would love to know.
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Tony P

Support Staff
Please stay on topic. This thread is about the Viper knockoffs and is a user's personal review of it. Please create unique threads if you wish to review a similar (or different) product
I'd bet the farm the light you linked to is the same as what I bought on ebay. I found ZERO identifying markings on any of the components on the PCB. It would be impossible to distinguish one from another.

I sent two lights to Wilson to do an LED swap (turn a white/amber and red/red into a red/amber and red/white). Once I get those back, I'll install them and update further.


Just Another Faceless Member
Silver Supporter
... If someone can clue me in to an actual industry standard of warning light brightness...I would love to know.
If you can get a real S2, you could put it through your same test procedure (assuming you could get a similar pattern on it).

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