For the Mi9 is this Hexagon 3D Flex Bumper.
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Weighing in at 10g the new TPU bumper is primarily for the new Mi9, but will also fit the Mi7 and Mi8. It is designed to give a great fit for the popular Xtreme Twister/Speciale body's, and also looks great too!
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The bumper has a 10mm longer protrusion so gives a better fit for the modern method of forward mounted bodies. No more need for extra bumper foam!
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The flexible design provides great impact resistance too.