These are Archee McPhee's pre-made Tin-Foil Hats for humans ($8.50) and cats ($7.50). They look like they'll protect you from government mind-control and alien probing, the only problem is THEY'RE MADE OUT OF MYLAR. Now that's just shoddy product design. What good is a tin-foil hat that only LOOKS tin-foil? That's like expecting to stop real bullets with the bulletproof vest that came in a $40 SWAT Team member Halloween costume (just FYI I already have one if you want to do a group thing this year). You might as well carry around a sign that reads 'Free brain for probing'. WHICH I DO. "You're the master of reverse psychology, GW." I really am. Now don't hug and kiss me. I mean it!
Keep going for the cat hat, which looks significantly less like the tip of a robot condom than the human version. At least they're felt-lined and come with a chin strap.
Thanks to Christina D, who agrees you might as well wrap your head in duct tape and hope for the the best.