There are a few things to consider when choosing Aero bars. The first is the width of your handlebars. Most Aero bars are designed to fit handlebars that are between 42cm and 44cm wide. If your handlebars are wider or narrower than this, you may have difficulty finding a set of bars that will fit properly. The second thing to consider is the type of riding you'll be doing. If you're mainly going to be using your bike for triathlons or time trials, then you'll want a set of bars that offer an aerodynamic advantage. However, if you're mostly going to be riding on the road, then you may want a set of bars that offer more comfort and control. There are many different types of Aero bars available, so it's important to choose the ones that best suit your needs.