Tell me about weighted blankets

[Mapletreelane]

It is my SIL's 50th soon, she is the lady who has everything and I am struggling for present ideas. She loves throws and blankets so someone has suggested a weighted blanket. They sound good but not really sure how they work or if the benefits are real. Any experiences / recommendations most welcome. Thank you

I bought my DD14 a lovely pink fluffy one for Christmas it is a medium weight and is filled with little glass beads. Decent quality you can’t feel the beads just the weighted soft fabric.
She loves it and often sleeps under it and says it helps her feel snug and safe.
I can’t say if it helps her anxiety but she has used it a lot. I’m not sure if it’s a slobbing around on the sofa type gift as they are heavy it’s more for on the bed in my opinion.