Fujifilm X-T1 IR has a Fujifilm X lens mount and currently there are 32 native lenses available for this mount.
Fujifilm X-T1 IR doesn't have a sensor based image stabilization system but 8 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 1.5× 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