It's a magnet. In theory, when reaching a new level, you get one. It's kind of hit and miss whether someone gets them or not.
On those cruises that are not "milestone" cruises (reaching new CC level) we're supposed to be receiving art cards (pictures of the ships). But, again, sometimes they come, sometimes they don't.
We did B2B to become Plainum in 2013. We did receive 1 Platinum magnet (all 3 family members are Platinum, so shouldn't we have gotten 3?) and did not receive anything for our other pre-Platinum cruise.
I tend to look at anything we get in the mail from DCL as a bonus and not expect a thing. Over the years we've gotten some neat stuff from DCL in the mail over the years (CD of music, magnets, stickers, etc) and it's always a welcome bit of magic!
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