Not sure if this is in the right forum, feel free to move to the right one if im wrong

I have bought a bed roll (no idea what they are really called), but you put bub between two rolls so they cant move, or turn by accident etc.

Was wondering if any one else has one, or uses them and how you find them?

MIL never knew about them until i showed her. My sister used them for all 3 of her kids. I asked in my birthing class what SID's had to say about them, but the teacher wasnt sure, but is going to find out before next weeks class.

Any thoughts or ideas on them??