the foil faced bubble wrap stuff? never knew what it was called. it works great. Used 3m spray on adhesive to glue it on. Painted what we thought the birds might see. Everything under the front of blind we didn't paint. reflects the heat really well. Its a lot easier to mess with than the foam board.
"If there is anything with more thrill in it than seeing a flock of Canada geese with set wings coming straight at you I wouldn't know what it is. I haven't found it." Ray Holland