SureFire U2 serial numbers

There has been a lot of debate over SureFire U2's over the past few weeks, however one point stood out to me (forgot now who made it) about the serial numbers - low numbers being better.

My colleagues U2 is numbered in the 600's and is daylight white at all levels (almost no colour shift) and has barely any doughnut hole. Now there have been some problems with U2's and I would be very interested in hearing about any good or bad ones and what the serial number are. I have a theory that due to the demand for U2's, that they were being rushed out to meet orders without the care in manufacturing that they should have had, and that the 'first run' were built to a higher standard.

I think that this would interest all potential U2 buyers as well as highlight any possible problems. Perhaps you could list your serial number and any observations (good/bad beam, dirt under glass and tint).

Lets have your feedback!

Ian

A01673 here in Malaysia.
- greenish on lowest level, warm white on other levels.
- dirt and dust under lens.
- donut hole exists and obvious on low beam.
- clickie works fine.
- am happy with my light /ubbthreads/images/graemlins/smile.gif

A04333 here.

-Greenish on low levels (1,2), warm white on higher ones
-no dirt or dust
-practically no donut
-Clickie sometimes sticks in the "on" position (waiting for replacement)

Very happy. Just need that new tailcap.

Just to point out that the serial number is only a way to identify each flashlight from the others and not a way to identify batches or whatever.
Since the bodies have the serial number for the U2 it makes this even less likely that serial number can be used to spot characteristics.

Al

Just received my U2 today from LaPoliceGear.com in a new sealed box.

A01669
- almost or no color shift
- no dirt and dust under lens.
- donut hole exists and obvious on low beam.
- clickie works fine.
- am happy with my light

isnt the serial number to track dealers who undercut the market? Someone told me the serial was so that surefire could pick up a U2 off ebay, and know which dealer is breaking the rules. Then the dealer would be cut off from their supply...i dunno if this is true.

My unit's S#: A01067

-- Slightly green at lowest level

-- Had a bad tailcap, just got replacement today, works perfectly

-- Bright white on high, not as impressive as my L4, maybe it's the size or I got lucky with my L4, but I love the variable levels--- has great throw!!

-- I'm happy, it's an awesome light!

AO1569
Tailcap replaced
Small doughnut hole
Dust under lens
Fairly bright on all levels

I must admit I'm a little disappointed with the overall quality of this one especially for the price I paid.

Serial #A05453
I bought this about 1 year ago.
I don't have a huge amount of LED experience to compare it to, but I think it's a very white beam

another thing that would be interesting to figure out is...
I hear that different U2s have different tube sizes. Maybe we can narrow down where the cutoff is in the serial numbers.

Here are pics of my u2:
https://www.candlepowerforums.com/threads/138715

Just fyi tenfour, here is the U2 registration thread for you

https://www.candlepowerforums.com/threads/110169