Item # PP050821W, 1/4 Inch (in) Stem Outside Diameter and 1/8 Inch (in) Thread Size White Polypropylene Stem Adapter Fitting On Seelye Acquisitions, Inc.
Carbon Fork Shim 1 1/4 To 1 1/8 Steerer Tube Adapter 31.8mm To 28.6mm Stem Red | eBay
Amazon.com : Suncentech Bike Stem 120 Degree Adjustable Bicycle Stem 1" / 1.25" Handlebar Riser Adapter for Road Bike, Mountain Bike, MTB, BMX, Cycling (95, Handlebar Diameter 25.4mm/1") : Sports & Outdoors
Amazon.com : M:Part Threadless stem Shim Adapter 1-1/8 inch / 28.6 mm to 1 inch / 25.4 mm : Sports & Outdoors