The Brynje Super Thermo C-Shirt is a mesh base layer that shifts moisture away from your body well while adding just a touch of insulation.
It's made from Isolfil Merkalon polypropylene and the yarn is made up of loosely twisted smaller strands, so there's a large surface area to draw sweat away from your skin and shift it outwards, which it does very effectively. Although polypropylene moves moisture, it doesn't absorb it, so this base layer dries out really fast.
If you get a close fit – and that's not difficult because the Super Thermo C-Shirt is very stretchy – the mesh structure will trap a layer of air around your body for insulation. Being sleeveless, it doesn't provide masses of warmth, but I found it about right for cooler summer rides (or spring and autumn) when the temperature is in the high teens (°C). Brynje also have a Micro C-Shirt in a thinner weave that's suitable for warmer temperatures.
Start to overheat and opening the zip on your jersey gets rid of that insulating air immediately – quicker than with a solid-knit base layer – and dries off sweat faster.
All the seams are flat so you can't feel them in use, and although this isn't a cycle-specific cut I didn't have any problems with gaps around the lower back.
Also available in black and in T-shirt (£32), long sleeve (£39) and zipped (£49) options, and in various styles with wind-resistant panels.
Lightweight polypropylene base layer that shifts moisture well and dries out very fast.
road.cc test report
Make and model: Brynje Super Thermo C-shirt
Size tested: M
Brynje say, "A favourite among cyclist and summer hikers. Lightweight, super efficient moisture transport capability, insulates and dries better than anything. To maximise capabilities, use in conjunction with another top with a zip to vent, such as a cycling top or another Brynje product.
Use: All sports from cycling, skiing to fishing, but truly excels in high intensity activities."
Tell us some more about the technical aspects of the product?
Polypropylene doesn't absorb moisture, it just moves it, so this base layer doesn't get heavy with sweat and it dries super-quick.
The construction is good, although there's not a great deal to get right or wrong here.
I really rate polypropylene as a base layer fabric because it doesn't absorb moisture. Occasionally, it can feel a bit scratchy, but not here.
Tell us what you particularly liked about the product
The fabric works really well.
Tell us what you particularly disliked about the product
Not a lot. A string vest – sorry, 'a mesh base layer' – doesn't win any prizes for looking cool, but you can't argue with the performance.
Did you enjoy using the product? Yes.
Would you consider buying the product? Yes.
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 20+ years, and been editor of 220 Triathlon and Cycling Plus. He's been road.cc technical editor for eight 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.