Designed to harmoniously attach to Wolf Tooth's B-RAD Mounting Base, the B-RAD Double Bottle Cage Adapter allows you to carry two water bottles in a side-by-side fashion, so you can stay hydrated on longer hauls and trail rides. As a nifty alternative, you can use the B-RAD Double Bottle Cage Adapter to attach one water bottle alongside a Mini Strap and Accessory Mount (sold separately) for greater storage of tools and tubes in remote riding locales. To install, you'll need to purchase a separately available B-Rad Mounting Base (most likely the B-RAD 3 or 4 Base), which attaches directly to standard 64 millimeter bottle cage braze-ons located on your bike's downtube or fork leg. The Double Bottle Cage Adapter is comprised of 6061-T6 aluminum brackets and stainless steel hardware.