Amazon.com : NEEWER Mini Follow Focus with A/B Stops, Lens Gear Ring, 15mm Rod & Rod Clamp for Cinema Camera, DSLR/Mirrorless Camera, Compatible with Lens Diameter Up to 114mm, PG001 (Silver) :
Follow Focus Gear for FF-T05 - 6mm 0.8mm 64-tooth | Tilta
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Follow Focus Gear Rings (seamless flexible) for Vintage, Lens mod | eBay
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