Sony headphone identification guide
Which Sony WH-1000XM Do I Have? XM3, XM4, XM5 or XM6
Sony's WH-1000XM generations look related, but their exterior shapes are different enough that precision-cut skins are not interchangeable.
The four supported WH models
Check the model name, not just the shape
Because the WH family shares a common design language, the safest method is to check the actual model name on your purchase records, connected-device information or the markings supplied with the headphones.
Why this matters for vinyl skins
XM3/XM4 use one style of cup and ring layout, XM5 changes the geometry significantly, and XM6 has its own template. A skin that is a few millimetres out will not align correctly around the intended surfaces.