Forte Threadless Stem Adapter (1-1/8" to 1-1/8") - Performance Bicycle
Amazon.com: Bike Stem Riser, MTB Handlebar Riser Extender Bicycle Aluminium Alloy Head up Adapter for Mountain Bike, Road Bike, MTB, BMX (New, Black) : Sports & Outdoors
adapter from quill stem to ahead stem | Messingschlager