LED INDICATORS

Since having fitted LED indicators to my JPN I've gone through 3 LED specific flasher units.
The LED bulbs need to be Neg earth but I'm wondering now if the flasher unit itself is polarity sensetive too.
Any idea's from you guys with electronic minds ?
The flasher units I've used so far have not mentioned anything about polarity but I'm starting to wonder, surely it's not vibration thats killing them?

Mac.

if flasher unit worked the LEDs for even a moment then it ain't polarity issue as that would burn up right away or just not light at all. Check out Bulbsthatlastforever online if nothing else works out for ya. Bruce IIRC started his kits for Commando first and mine worked great for a few years even crashing on the LEDs to crack some off/apart but the survivers were still plenty bright. Sold it off to another as I got a all in one wireing box that had LED function built in.