Blder Sevenwrote a review of Castelli Thermoflex Arm Warmer on March 26, 2018
Familiarity: I've put it through the wringer
Needed to replace my arm warmers and opted for the Castelli Thermoflex version. I'm basically a standard XL in everything Castelli and the arm warmers fit perfectly. This version is quite nice due to the rubber grippers on the inside and outside of the top of the warmer and the "cuff" at the bottom that I feel improves the comfort and fit - and the micro fleece, red lined interior on the cuffs is a nice touch. I have long arms and the XL basically goes from the top of my arm to my wrist for full coverage. I tried the L on to see how the fit would be and could not get it over my elbows. The only other info I'd like to add if you are reading this is to not wear arm warmers with sleeveless jerseys or tank tops, unless you are trying to make other people laugh intentionally. Bottom line is if you get the right fit on these arm warmers, you won't be disappointed with the quality and durability.