Originally Posted by
bearisgray
Definitely Do Not Use Insulbrite in them.
It should be Insul-Bright
https://warmcompany.com/products/warm-home/insul-bright
The following one puts the "do not use in microwave" in capital letters and red print.
https://www.kalquilts.com/W3005/Summ...-15-metre-roll
The reason why is that it contains reflective mylar - which is a reflective metalized polyester film - which does not behave well in a microwave oven.