I'm not a big fan of addons, but my Zoom ring on my Lumix 35-100 F2.8 started to wear out. As you may know, a zoom ring is usually a big rubber band. You can carefully work it off and replace it or clean it, depending on the lens. A new part was about $25, so I looked around and found the Band.It aftermarket zoom rings for the same price or less. It's big, chunky, easy to turn and very grippy. A quality product. It isn't streamlined, but the grip is much easier than the stock band.
https://www.camerabandit.com/
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