In my experience, there is no good label to add to LTO tapes.
I started using either a white marker or paint pen when needing to add
information to the tapes.

If you MUST put an extra label on the tapes, I suggest some lablels I
have run across, they are VERY thin plastic/mylar with perminant type
adhesive.

I did, long ago now, try other stickers on some LTO tapes for a similar
reason, and managed to get an LTO drive gummed up inside.  Not a pretty
site, and I was nicely but firmly chastized my my IBM service person too
:( ... We all like to keep them happy.
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