The Castelli Uno: Uno Plasma is a close-fitting long sleeved base layer for the cooler weather that provides good moisture management.
It's 100% polyester and the fabric has been given a 'nano-plasma' treatment to help take moisture from your skin and spread it out to aid evaporation.
Nano-plasma treatment? Okay, we had to ask too. Castelli told us that the fabric goes into a machine the size of a small delivery van, then the air is pumped out so there's a vacuum in there. Then the fabric is bombarded with plasma (a highly ionized gas) that simply roughens up (it's a scientific term) the surface of the polyester fibres, creating more surface area so that water will get drawn away from your skin and transfer away. It's not a chemical treatment that'll get washed out gradually, it's a permanent modification.
I found the cut spot on. The arms were long enough to keep my wrists covered and the collar tall enough to prevent cold air getting in there. It's a close fit – it sits right next to your skin without too many folds or ridges – even on skinny whippets. Of course, we're all different sizes but the fact that the weave is so stretchy means that this base layer will fit a whole range of riders without trouble.
The seams aren't flat-stitched but I can't say they bothered me. I didn't even notice them in use.
The Uno: Uno Plasma does a good job of picking up sweat and shifting it away. I've known lighter base layers that dry a little quicker but, unlike some, this one doesn't feel cold and uncomfortable when it's a bit damp. In fact, it scores highly for comfort at all times. Lots of polyester tops feel cold and plasticky; the Castelli doesn't actually feel synthetic.
This is medium weight as base layers go. It's not as light as a summer mesh base but it's not as heavy as a winter thermal one. Castelli give it a temperature rating of 8-14°C and that's reasonable. You probably wouldn't want a long-sleeved base layer on when the temperature's above about 14, although you could wear this when the temperature's below 8°C with the right outer layer(s).
Mid-weight autumn/spring base layer that manages moisture well.
road.cc test report
Make and model: Castelli Uno: Uno Plasma LS
Size tested: Large
Tell us what the product is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
Castelli say, "Nano-technology comes to base layers, in this case through a plasma treatment that causes moisture to wick immediately into the fibers and away from the skin. It is just warm enough to extend the comfort range of your favourite Castelli garments, but it looks good enough to be worn on its own for off-season cross training.
- Nano-plasma fabric actively moves moisture away from the skin
- Layer of air next to skin allows for maximum evaporation
- Minimal seams for maximum comfort"
Yeah, that's about right. It's a mid-weight base layer that's best in autumn/spring conditions.
Tell us some more about the technical aspects of the product?
If you want the full story on the plasma treatment, check out the abstract of this scientific paper.
Rate the product for quality of construction:
Long sleeve base layers start at about £25 or so. £45 is okay for something of this quality.
Tell us how the product performed overall when used for its designed purpose
It works really well to shift moisture away from your skin and it's reasonably comfortable even when damp.
Tell us what you particularly liked about the product
The feel and the fit.
Tell us what you particularly disliked about the product
There's nothing that stands out: it's a strong performer.
Did you enjoy using the product? Yes.
Would you consider buying the product? Possibly, although I must say that Craft make my favourite base layers.
Would you recommend the product to a friend? Yes.
About the tester
Age: 41 Height: 190cm Weight: 75kg
I usually ride: My best bike is:
I've been riding for: Over 20 years I ride: Most days I would class myself as: Expert
I regularly do the following types of riding: time trialling, commuting, club rides, sportives, general fitness riding,
Mat has worked for loads of bike magazines over the past 20 years, and been editor of 220 Triathlon and Cycling Plus. He's been road.cc technical editor for seven years, testing bikes, fettling the latest kit, and trying out the most up-to-the-minute clothing. We send him off around the world to get all the news from launches and shows too. He has won his category in Ironman UK 70.3 and finished on the podium in both marathons he has run. Mat is a Cambridge graduate who did a post-grad in magazine journalism, and he is a past winner of the Cycling Media Award for Specialist Online Writer.