All Crupi Moto Aluminum Expert bars feature 6061 Butted tubing to keep them strong and light. All bars in this size category have an 8 degree sweep with 1 degree of up-sweep. All of these handlebars are recommended for riders under the weight of 150lbs. If you are close to 150lbs or over this limit, you should be looking at chromoly bars.
The Moto 4.5X" bars are perfect for Expert frames and great Junior and Expert Cruiser bars. The Moto 5.5 and 6.5 bars are better for riders on Expert XL frames or smaller riders on a Pro frame