I’m prepping to dive into FBA on a few of my non-personalized products. They are mostly flat and I package in sealed cellophane bags. I’m seeing that poly bags need suffocation warning, but is cellophane ok without the warning?
Any advice on packaging flat items (sticker sheets mostly) for FBA would be welcome 
Amazon requires that poly bags be at least 1.5 mil thick, and Poly bags with a 5-inch opening or larger (measured when flat) must have a suffocation warning labels. These can be preprinted bags, stickers, or printed messages.
Personally, we never used poly bags less than 2 mil and actually prefer clear polypropylene bags, because they are stronger and make our products sparkle. But they are also more expensive.
You’re welcome, and best wishes.