Over the years, we have made numerous renditions of the classic european baselayer. you know the ones cool mesh ones all the pro cyclist wear..you know why..cause the keep the body cool, the provide 1 more layer of protection, well something in case of a crash. Once you wear one of these, you never wear a t-shirt again under your jersey! For 2015 we found in Italy the premier circular knit company who makes these for the majority of the Pro Cycling Teams and clothing companies. We kept it basic as do you really different zones to keep you cool..nope. And we are pricing it to really offset the costs of sponsoring the Axeon U23 Team as opposed to copeting dollar for dollar with the big boys. Same manufacturer, just no middle man to you! Unfortunately we only have the main M/L size until at least the fall. This size will fit the majority of people. A snug fit regardless of size, the difference is it may run LONG, which for most people is not a problem when worn with bib shorts.