Note that these jerseys are from the same vendor we used for the Horsey Hundred, but in the men's jerseys we've moved to their larger sizing line. People who have tried the jerseys on say that they fit similar to other jerseys. For help with sizing, you can contact Giordana here: https://custom.giordanacycling.com/pages/custom-inquiry - Note that they also have a chat function you can use during normal daytime business hours to ask questions. If you do inquire of Giordana about sizing, please tell them the line is Super Fit if you're inquiring about a men's jersey and Vero Pro if you're inquiring about a women's jersey.