Marshmallows are made of foamy cells with air inside so you can crush them with high pressure and they'll expand again as air rushes out of the bottle. Examine the join where the valve goes ...

The aluminum foam panels can be resin coated ... x 10’, 4’ x12’) ALFG-12.7-LM Natural also available – With cells closed is also available in thicknesses of: 12.7mm & 25.4mm ...