It’ll work, but doesn’t run very well. It operates at a higher VF so you’ll get less efficiency. You lose 40% output very quickly. Stick with what’s in it
This is with the 8*7135 biscotti driver. Used this in my first lot of stock when I first started using the Osram red. I stopped after running this test.
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Here is the new driver in the L21B
My review of the H2 headlamp. Thanks Simon for sending it
Have a good holiday Simon!
Simon, thank you for producing these colorfu C8+’s! They are delightful, especially with diffusers.
This must be one of the most beautiful beam shots Ive ever seen. Your use of a wall corner to mix 90 degree beam and color convergence was brilliant. If its a Photoshop, it certainly fooled me. Well done!
Thank you! I’m quite proud of how that turned out. The only editing was cropping it into a square, haha.
The L8 tube doesn’t fit the M3 or the L7 unfortunately
will b35am be available in warmer temps? 2700-3000k?
Hi, Simon, I hope you’re enjoying your holidays! Any plans for s21d with clear narrow optics? And what about putting 519a in?
I like this idea, but I would prefer narrow frosted optics.
Also, I would settle for an S12 with 519A’s.
Simon, any chance you would stock 519A in 5000K (or other temperatures) in the future?
Some modders reported very good results slicing the 519A, which has the side effect of lowering the temperature. Thus, to start with a 5000K emitter should give an end result of about 4500K, which is desirable for many.
Happy New Year, Simon 
If the 519As become available in the S2+ (and other lights) in a range of colour temperatures from 2700k to 6500k, I can see myself buying quite a few for night photography (replacing my LH351Ds).
Since we’re talking about our hopes for the 519A…(as long as 519A has the similar brightness and better tint than LH351D )
I’m hoping for S21D 519A 3500k 
Sign me up, I had one with 219Bs in my cart before Simon pulled em out.
Also - 519A emitters in S2+ hosts please. A shorty S2+ with a 519A is a tantalizing idea.
Simon, did you ever get a round to do some measurements? If not, I’m assuming you’re enjoying a well deserved vacation 
+1
Would love to have a high CRI alternative to the LH351D in various temperatures. Already have too many LH351Ds and I’m done with SST-20, which is too narrow beam and only 2700 and 4000K (low CRI of colder ones is a no go).
I remember when Simon released the driver first red W1 Osram, and iirc it was made more so for the lower voltage frequency of that LED not necessarily the low amps.
Couldn't a red W2 be used with 8*7135 more efficiently? I have used a couple, but I've never looked up what they're Vf is.
2000k gt fc40 ?! Sign me up!
Me too!
One for me too, with the ability to run without the battery inside (just using the USB cable), pretty please