What sleep positioner products are best?

[Guest guest]

At 7 weeks, I just took my twins to the pediatrician because I was concerned

about their flat heads. The pediatrician stated they have plagiocephaly and

stated that we need to try the precurser steps before banding - tummy time,

sleep positioner, no swing.

What are the best sleep positioners? Please let me know which ones you as

parents recommend as well as which ones you felt did not work.

Thanks!

Patti