This is a Tamron-made lens that is equipped with a Fujifilm X mount. Thanks to the image stabiliser, you can use higher shutter speeds without risk of blurry images.
From London Camera Exchange
Tamron 150-500mm F/5-6.7 Di III VC VXD ultra telephoto zoom lens - Fujifilm X fit
Wilkinson Cameras
Tamron AF 150-500mm f/5-6.7 Di III VC VXD Lens - Fuji X
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