The Lone Peak Handlebar Rain Cover is designed to cover the Alta or the Mt. Baldy handlebar bag. Made from a waterproof 210 D oxford in a bright yellow, we sew it up and seal the seams. The cover is designed to go over the front of the bag and cinch up around the back. This helps you get to about 98% rain proof. with the back open around the mounting bracket, there is a chance some moisture will get in. But its is light and packs small so you can stow it in a side pocket and pull out if needed. https://lonepeakpacks.com/pr...