Blendr Adapter for XXX Stem Clean up your Bontrager XXX stem cockpit with a Blendr XXX base. Blendr is represented by the following simple equation: Stem + Base + Mount. Add accessories. Product details Blendr is represented by the following simple equation: Stem + Base + Mount. Add accessories. Base for use with previous XXX Stem (single pinch bolt) Mounts for beautiful, integrated accessory attachment (accessories sold separately) Bontrager XXX Stem Blendr Duo Base (for older models) Model 25911