50 Sheets A4 Premium 800 Micron 0.8mm GREYBOARD Thick Strong Backing Card Craft

I use these to protect my art prints in the post. Haven’t had any problems so far (bought these about 6 month ago) they aren’t very thick but they do the job

Nice quality greyboard and just right for my book projects like Goldie locks and the porridge not too thick and not too thin in fact it's just right