HEAT WARNING FOR USE WHEN YOU FIND AN ANIMAL IN A CLOSED HOT CAR
This warning is for use within Idaho and pertains to Idaho codes. Your state may have similar codes. Please check with your state's Statutes. I print this out on bright yellow paper and stick in under the driver's windshield wiper facing in. That way they see the warning.
See below for link to Idaho Codes.
You may download this .jpg file for printing.
Idaho Codes mentioned on above form