NZ 2015 Coloured 50 Cent Has Arrived

[Fulvio]

Plastic. not sure exactly what plastic but pvc free

Polypropylene (PP), IIRC from previous discussions.

BoPET (Mylar is one of several brand names) isn't stiff enough for this application. Look at a packet of chips or a helium balloon to see what I mean.

Also, I would be really hesitant to leave coins in such a holder long term, for the same reason the MYO cards are a bad idea. Anything that's open will let air in, along with all the contaminants it contains. This will eventually kill the coins.