I, like others, was a little annoyed that my BTU didn’t come with the AR lens it was suppose to have. But I thought it wasn’t that big of a deal. However testing done a couple weeks ago without a lens showed it should benefit from a quality lens.
So I started hunting everywhere for one. Flashlight sites, scientific optic suppliers, etc., all without luck.
Well it just snapped to me after looking at my light case with my BTU and SR90 sitting an inch apart. Duh… Maybe the SR90 lens would fit? So I took some measurements and it looked promising. Close enough to give it a shot. So I called Olight to see if they had a lens and if they would sell it to me. They said sure. So a week later I have it in my hands.
They call the lens a ultra clear lens, non-reflective, anti-shattering, with 99% effective transmittion.
The lens turns out to be almost identical in size to the BTU. Though both could benefit being a couple mm bigger. But still, this one fits as well as the stock BTU lens.
So I charged the batteries up and started testing. The results -
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Stock lens - 2835otf at 30sec., and 126K (test at 15m)
UCL lens - 2975otf at 30sec, and 132K (test at 15m)
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And the UCL lens was done just a couple minutes after the stock lens test, so it likely would have been slightly better with room temperature LED’s.
So there you go - a proven 140 lumen gain with a quality lens.
And this lens was reasonably priced too. Cost $10 + $5 freight = $15 to my door. Now the catch is I don’t know how many of these SR90 len’s Olight will sell. I actually have a SR90 and told them I needed a replacement for it. So it went smooth for me. But anybody else wanting this lens - its up to you how creative you want to be at requesting one. But I promise you it’s a sweet lens and great mod for your BTU.
Thanks rdr, I’ll give it a shot.
Could you post a link ?
Nope. They don’t carry a lens that big unfortunately.
I got mine from -
http://www.olightusa.com/
But you can likely try any of the bigger Olight distributers. Or Olightworld themselves.
thanks front . i always said the btu lens was full of imputities . the cheaper the lens the more millions of of microscopic bubbles and impuritie in it thus this blocks out light coming out . I very surprised that the sr90 lens fits in the btu! thats a shocker for me.
Im worried with all of us going to olight with all sorts of made up stories of how we lost our sr90 lens and need a replacement will freak out the staff at olight lolzzz!! And i looked all over ebay / googled lots and cnt find any seller with a sr90 lens .
I emailed Olightusa first. Got a response the next day saying yeah they had one and for me to call them to order it the next day. Oddly the guy on the email told me it would $29. I had a family member call them the next day to order it. They told her no problem, but it was only $10. So she ordered it. It took about 3 days to show up. It was well packed. In a sealed sleeve, rapped in foam, in box stuffed with foam pcs.
There are several Olight sources out there. Olightworld, Olightusa, Olight-USA, etc. So maybe it won’t be to bad getting some.
:bigsmile:
i have emailed them and awaiting their response eagerly . With my upgrade to u3 and this lens upgrade ,i think my btu is pumping out the most lumens right now muahahah .looosers
(im still never buying anything from Ric ,I was a very good customer for him and least he could have given was a AR coated lens
)
lolzz .Ryan hows the situation there buddy .i hear there's a war about to start? pray that everything works out and there's peace in the Korean peninsular
Not the first time this has happened, so we’re all good. :cowboy_hat_face:
Thankfully I do have a US citizenship, so I’ll run to the US embassy if it does break out. 
Rayan please dont run to the us embassy .im sure thats the first place theyl bomb ??duhhh !!!
iv been following the Korean war since watching "Mash " as a kid . what im amused about is how near Seoul is to the border! all the 12000 north Korean artillery pointing at 30 million people!!!
iv seen pictures of north Korean soldiers and they look starved . they can see the prettier fully developed southern ladies/i phones/cakes/tons of electronics /LED LIGHTS LOLZZ across the border! Now they l be like zombies trying to get all these once a war does start! iv been thinking of this for a long time! phew finally got it off my chest .feels good . anyhow wish you luck bro. I am familiar with UN peacekeeping duties around the world and so have seen my share of destruction.its sad
(Do you think kim jon will be shocked if i send a BTU shocker to him? 
How easy was it to replace the lens on the BTU? Also, if it’s not too much of a hassle, since the lenses are too short, can you give us the exact diameter and thickness of the lens you recommend? I’m thinking about ordering a custom AR acrylic lens.
Thanks!
EDIT: I got the lens measurements form_the_’s exhaustive review:
Lens diameter: 94mm
Lens thickness: 3mm
How much wider would you suggest the lens be (96mm)? I assume the thickness is correct.
I heard they have an underground bunker… I may be wrong, though. 
Just to clarify which lens I’m custom ordering, it’s the UCLp AR Acrylic Lens from flashlightlens.com - assuming the price isn’t prohibitive.
I’d say 96mm would be a good size. The acrylic lens I don’t have any experience with, so I don’t know how well it will compare or hold up to my glass UCL lens. But if the will get you one for a reasonable price, its would be a reasonable choice to try.
So you are no longer buying anything from him because he didn't give you something not in the description of the item for sale?
I personally have no issue buying from Ric again. The BTU is a beast of a light with its only comparable rival being the TK75 when power, throw, price, quality, and flood are all considered.
And truthfully, the BTU comes closer to matching its advertised specs than 90% of the Chinese seller lights on the market.
That’s the way I look at it.
But Shaquille’s money, is his money, so if he’s not satisfied with the sale Ric made to him, I guess that his choice. I can understand that.
But I personally think I bought an awesome light for money from Ric.