Review on 🚲 Fengek 15 Pcs Headset Spacer: Carbon Fiber Road Bicycle Stem Headset Spacers Kit for 1-1/8 Inch Stem, 7 Sizes - 1mm to 20mm by Scott Spoja

At first I thought all stem spacers worked the same and there was no price difference. I'm so wrong. This may seem like a great stock seal with so many different sizes, but personally I would not use seals smaller than 5mm as they are too thin and provide no support when mounting with a butt plate. The gasket is too soft even for the thicker ones where it bulges slightly when tightening the stem cap. Instead I bought an aluminum spacer which is more durable than this spacer. I would not recommend it.