Useful adapters,first time I’ve seen them in this design ,from China.

Fork Stem Extender Handlebar Riser Aluminum Alloy Bike Extension Durable | eBay
Hidden Stem Extender. 1 x Stem Extender. This product can increase the handlebar height by about 3cm. Material: Aluminum alloy. Made of high quality material, durable and practical to use. Size: About 81 28.6mm(As Pictures Show).
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