those are "EFT" ones from FOSS, the tubes have been one of the highlights on the 2012 Taipeh international bicycle show.
"pfft....simple tire tubes...how interesting...not" you might say now...
but hey, those tubes ARE kinda interesting because they are unusual and unique because they follow a different concept than the usual tubes. standard tubes are made of vulcanized rubber, there are also lightweight ones made of either latex or butyl, but the ones I got are made of TPE (thermoplastic elastomer).you can already tell the difference by the look:
yeup..they are transparent! now I just need also transparent tires, then everyone can see!
nah, the actual reason why I am gonna test those tubes is that they are 33% lighter than rubber tubes, but without the "look at me too hard an I will go flat" issues of the latex- or butyl- lightweight tubes (those are also not really made for the dimensions of the fat tires I use).
they seem to have even a way better puncture protection than thick and heavy rubber tubes because the material is not expanding when the tire is inflated, so there is no surface tension which makes a puncture hole open wider than the object that punctured it. because of that the object puncturing the tube is enclosed so no (or just a little) air loss appears. ok, that's what FOSS (the manufacturer) says, time will tell how well that works IRL.
the only downside is (besides the price, which is 3 times the one of a standard tube) the mounting which needs more work and you obviously have to pay a lot more attention during the process because the tube (and the included rim tape) have a defined movement direction, the tube is also glued to the rim tape, so you can not fiddle it a little back and forth anymore after you mounted the tire when you haven't worked that precisely at the start.
one point in the manual sounds a bit wrong and could be misunderstood:
due to the glue method the valve comes without a thread which gives it a pretty cool look:
I also got the special patches for the tubes which work like simple stickers:
