For some reason, a goofy old high school memory just came back to me the other day (I'm 35)... This kid who liked to fight all the time came to school one day with 4 "C" cell batteries taped in pairs, end-to-end. He said that if he got into a fight, he'd put these in his hands to "make his punches harder". I don't think he ever used them. My godfather was telling me a few months ago that as a kid, he used to take the big packs of Wrigley chewing gum and squeeze them in his hands for more solid punches. Once again, he didn't mention if he ever used those. I'm familiar with brass knucks and the like, but they give the knuckles a solid covering. Does a heavier or bulkier (in the case of the gum) inside the hands help anything at all? I tried the batteries the other day on the heavy bag, and I made a few observations: Wrapping my fingers around the battery made my thumb "lay" in a different spot of my fist, so when I hit the bag with a straight my knuckles impacted on a different area, and the tip of my thumb also hit the bag. Not a good thing, IMO... My forearms got tired a lot quicker, since I used them more to keep the batteries squeezed in my hands. I never realized how much I keep my fists relaxed until they make impact. This taught me something about my technique... Throwing a left lead hook with vertical knuckles, I hit with the tips of my middle knuckles and my wrist twisted back. This had to do with the changing of my knuckle angle from holding the batteries. Luckily, I wasn't hitting full-force, or I would be typing this with my right hand only... If used in a real fight, there's no doubt that they'd be very temporary if grappling were involved - or even a hindrance. I don't think I hit more solidly with them, because they changed a lot of my punching technique. Perhaps with more practice, but I think I'll just write this one off as a schoolyard myth. What do you stand-up experts think? Effective or not?