Fujifilm X-T1 IR has a Fujifilm X lens mount and currently there are 50 native lenses available for this mount.
Fujifilm X-T1 IR doesn't have a sensor based image stabilization system but 12 of these lenses already comes with optical image stabilization.
Since Fujifilm X-T1 IR has a APS-C sensor, it has a focal length multiplier of 1.5x so you have to multiply lenses original focal length with this multiplier to find the Full Frame equivalent focal length of the lens when mounted on X-T1 IR.
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Fujifilm X-T1 IR Lenses with Image Stabilization
Fujifilm X-T1 IR Lenses with Weather Sealings