The Bontrager Madone Bar/ Stem Blendr Duo Base lets you add compatible Blendr accessory mounts to the Madone KVF Aero Integrated Bar/ Stem. The Due base allows for the attachment of a two Blendr accessory mounts so you can securely attach a computer & light or camera to your stem. Features Blendr works with this simple formula: Stem + Base + Mount. Add accessory Bases for use with the Madone KVF Aero Integrated Bar/ Stem Add any accessory mount (sold separately) for an elegant, integrated look