I've used plenty of sticks over the years, primarily whilst walking, and often in the snow. One of the main issues with them is that if you are out with a small bag, whilst running or on a day walk, for example, it's difficult to stow them when not using. The C4s are the first sticks I've had which pack down to such a small size that they are genuinely and practically portable on a small pack.

The poles gave plenty of confidence when crossing the above open rock slabs high in the German Alps.
 
When folded down they comprise three linked sections with a maximum length of 36cm. Think about that for a second, that's about 4cm longer than your standard school ruler. Easily small enough to go into most rucksacks. The secret lies in the fact that the top-most section has a 4th and 5th section inside it which slide out to enable the fully extended pole to go to 125cm. There is a plastic coated wire connecting the sections together.
 
To assemble the pole you need to connect the two lower sections together by means of a simple, snug, push fit. This then leaves a 10cm gap between sections 2 and the handle section which actually comprises sections 3, 4, and 5. Release the single clamp and pull out section 3 and connect to section 2 by means of a second snug push fit, and then, by holding section three firmly and pulling away from the handle, a spring-loaded button will pop out between sections 3 and 4. Sections 1, 2 and 3 are now locked together and can only be disassembled by releasing the spring button.  It's then a simple matter of sliding section 4 out of 5 to the required length, with 5cm increments marked on the pole from 105cm to 125cm. You lock the whole thing in place by closing the single clamp. It sounds like a complicated process, but it's actually quicker than any other pole I've ever used once you have the knack.
 
The grip is ergonomically shaped foam as you'd expect. Personally I'd have liked it to extend down the top section far enough to grip with two hands, but that's not a major quibble as you can, of course, still hold it with both hands above the clamp (I've found this to be useful when off-piste skiing and traversing steep ground). The wrist strap is another nifty innovation which takes a while to get your head around, but once you do, is super simple to understand. The strap is a single length of padded webbing, which narrows at each end. The ends pass into a recess in the handle and around a captive pin. One of the ends has a plastic edge welded to it with sharp plastic teeth. If you pull both of the ends simultaneously they both come out. You can then adjust to the length you want, and pull them back into the recess by pulling on the padded loop. The plastic wedge then locks the whole lot in place.
 
OK, that's the mechanics sorted. How were they in use? Well something of a revelation in actual fact. Though I have tried running with poles previously these are without doubt the best I've ever used. First and foremost the baskets on the ends of the poles are very small - 3cm, comparted with around 10cm for most others I've used. This means that they're easier to place, get stuck less, and also pack into your bag more easily. They are incredibly light - 217g per pole - thanks to their carbon shafts. On low to mid gradient ascents I was able to find a rhythm which took a huge weight off my knees and hips and onto my arms, and on technical, steep and rocky descents I was able to use them as extra arms to reach out in front and lower onto. It takes some practice, but running long distances with them felt like a bit of a personal revolution.

Putting the poles through their paces on some STEEP terrain in the Dolomites.
 
I should also mention the warranty that Kompardell offer as it's outstanding. On one run in Italy I started out up a dry river bed, caught a toe and fell heavily. Thankfully I was OK, but as I fell I swung one of my poles in an attempt to slow my fall, and the shaft of one of the lower sections struck a sharp rock edge, shattering the carbon and rendering the pole unusable. The downside to having carbon shafts is that you can't duct tape them back together until you get home, but the upside was that Kompardell offer a 3 year no quibbles replacement warranty on their poles so the offending section has been replaced free of charge and I am free to continue using them.

Half an hour before breaking one of the poles on a rock.
 
Carbon doesn’t corrode or fatigue like aluminium so I expect that these poles will last me for some time. My one suggestion to the manufacturers would be to supply them in a bag so that you can store them in your bag without fear of ripping the sides, or getting your stuff mucky.
 
SRP £159.95

More info on the Kompardell website