You couldn't buy a comic back when I was a tyke that didn't have a page near the back (possibly the inside cover) full of "novelty" items available by mail order. This is the specific iteration I remember. As I recall, the cheap plastic artifacts employed something like a diffraction grating that created a slight "ghosting" effect, such as you get when you remove the special glasses at a 3D matinee. "Look at your friend. Is that really his* body you 'see' under his clothes?** Loads of laughs and fun at parties."***

gullibly,

*"His." Yeah, right.

**Spoiler warning: No.

***The laughs referred to are to be heard at our parties, which are quite the lavish affairs, funded as they are by the allowances of untold thousands of credulous nippers like you.