This particular lens is equipped with an Olympus/Panasonic Micro 4:3 mount. The lens has a maximum ƒ/2.8-4 aperture and a minimum ƒ/22.
From London Camera Exchange
Panasonic Leica DG 50-200mm f2.8-4.0 Vario-Elmarit ASPH H-ES50200E
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