Been wearing my nice little DD flashlight for many many years now and i still like it very much but over the time ive ran out of QTC pills. Ive been looking for replacements but im having difficulties sourcing them. I have located a shop in the uk that offers a ‘comparable’ product but their shipping rated are prohibitive for something im not sure if its any good. Does anyone have a decent source for a couple of these little things that also ships to the EU?
I have a few in house for ages. Wanted to play with them at some point but never came round to that. You can have them if these are what you are looking for. Given your location there should be a way to get them to you 
What are QTC pills?
What’s a DD flashlight?
QTC = Quantum Tunneling Composite. It’s spongy material whose electrical resistance decreases with compression. Worth looking up if you like interesting science.
DD = Direct Drive.
In the OP’s case the battery is connected to the LED through the QTC pill, there is no driver (hence DD). When uncompressed the pill insulates and no current flows, as the pill is compressed it starts to conduct and the LED lights up, the more compressed the pill is more it conducts and the brighter the LED gets.
RepProdigious, do you have a link to that UK shop and product?
I’m in the UK, if you want to try it we could look at me getting some to forward on to you if that makes shipping costs acceptable.
@Sammys, that’s a great link there with excellent discussion of QTC.
Anybody know what happened to FrontPorchCarver?
I have a bunch of Peak lights with QTC and bought a bag of it back in the day. Great in concept but very finicky in practice. I moved on from the stuff, it’s very cool but the inconsistency and difficulty dialing in and holding a level dimmed my enthusiasm (couldn’t resist the pun) (couldn’t help that pun either, I have to stop).
Those look exactly like what im looking for! What do you want for them?
-edit oh and i dont live in amsterdam anymore…… moved like 3 times since 
Guess now is as good a time as any to update that 
If i cant work something out with djozz i might just take you up on that. Thanks for the offer!
I think djozz will have you covered But obv let me know if not.
Do you have a link though? I’m curious to see where it’s being sold.
If you get me your address, I will send them. No costs, I would not even know what they have cost me.
Holy cow, I went through my old emails and found where I ordered them, in 2011, and they seem to still have them in stock!!! https://mindsetsonline.co.uk/shop/pressure-sensitive-conductive-rubber-pack-of-5/ Hope it helps 
Agro planned to do a group guy some time ago. I would be up for some if somebody wants to do this. I asked mindsetsonline if they could use different shipping for international orders which could cost us less than $5 bucks.
I remember Match saying something like QTC material isn't all that great of a solution because QTC material isn't that durable.
That was pretty much my experience, very cool but very fiddly. Definitely seemed to degrade pretty quickly in the lights I had with it.
That is indeed the site i mentioned earlier with the questionable alternative at too high shipping (they are asking 15 pounds shipping and customs will add a nice sum over the combined total).
Its indeed not all that durable, it tends to crumble and does so faster when you put it in a twist flashlight between uneven surfaces. Ive fabricated two little parallel squish plates where the qtc can sit between so it only sees clean nicely spread out compression forces but even then the life of the material is limited.
That may not turn out to be the actual shipping. This is a excerpt from an email exchange I had with them from my 2011 order
I orderd some QTC Pills to the US and i just saw that your estimates shipping £35. My order is #XXXXXXX. If this is going to be the shipping cost i would like to cancel my order.
And the response
Hello,
The shipping will not be this much as we will send your order by Airmail.
This should only cost a few pounds.
Kind Regards
So maybe contact them and see?
Thanks to djozz i am now the proud owner of three brand sparkling new QTC pills
It should not be too difficult to see which is the new and which is the old one
These should last me another decade or so. Thanks a bunch man!