Adjustable mounting/positioning of two water bottles - works great!
I was going to give this 4 stars for that - but I chose to give it 5 stars, because it works so well for my application. From Wolf tooth: "The B-RAD system begins with a series of slotted Mounting Bases. Available in three sizes, B-RAD bases can shift a bottle cage away from inconvenient rear shocks, add room for tools or tubes below a bottle cage, or even provide space for a second bottle on sufficiently-long down tubes."
I paired this double bottle cage with a B-RAD 3-slot base, which allows me to mount 2 bottles on my Salsa Fargo downtube - just below a Relevate frame mid bag, and still leave room for another smaller accessory kit on the downtube. The double bottles (with old-school bottle cages) sit just above the 'normal' bottle mount; the bottles do not interfere with pedaling, and are very easy to access while pedaling. The base plate mounts to the frame, and the double barrel cage mounts to the base - and can be positioned where you want your bottle to be. The stock photos below come from Wolftooth
Works great! Converted single bottle rack into double bottle rack in about 5 minutes. Only reason it's not a 5 star review is the torx screws. Luckily, I had a bit that worked.