The 8 mm tube will not fit (directly) on focal plane shutter Hasselblad cameras (2000- and 200-series), but all other cameras (and on the 2000- and 200-series if it's not the only and not the first tube that goes on).
The problem is that the collar on it and the shutter speed ring are in each other's way.
The old style 10 mm tube has similar issue.

There are no issues with any of tubes with any of the lenses, except the 135 mm bellows head lens.