A core staple for any rider. Roubaix soft brushed fabric has an excellent combination of warmth and comfort. Elastic upper arm grip band keeps them in place.
Technology
Roubaix
Roubaix is a fast drying, super-stretchy, breathable fabric that couples a fine, soft polyester fleece to a nylon outer surface for the ultimate cold-weather riding protection. It is very durable and has excellent thermal features making it ideal cycle clothing covering areas of high movement such as knees and elbows.
Measure the circumference of your upper arm where the armwarmer/sunsleeve should sit.
Measure the length from where the upper and lower ends should sit.
If your circumference and length measurements don't match well, go with the circumference measurement as getting the tightness of the fit around the arm is the most important.