These 3d printed nylon shims are needed for mounting the Blue Ridge on any handlebar that doesn't have a 31.8mm or 35mm stem clamp. The most popular alternative size is 22.2mm, includes most custom bent Ti or steel handlebars, such as DOOM Bars. For older drop bars the 25.4mm is also sometimes useful.
The Blue Ridge comes with 31.8mm and 35mm shims already, so if your handlebars have that stem size then you're good to go!
