This week's Mail Order Monday is in honor of Shark Week. For just $5.95 you too can have SHARK POWER! Apparently they were expecting this to be so popular they had to include two order forms in the ad.
Based on this other ad, it seems SHARK POWER is the ability to manhandle sharks in any way you see fit. Not the most useful superpower, but maybe a little more manly than telepathically talking to fish.