I think I know what you are talking about. The screw head is actually round w/ 6 indentations. Means a hex driver will not work. Need a special driver. its just like the screws in the back of Nintendo type games.
If anyone knows where this type tool can be bought, I would like to know, too. Can't replace the batteries in those games w/o one.
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umm, no. the screws on the ti83+ are different. they need some sort of six
sided tool, like a tiny alan wrench, or hex screwdriver. unless you can find
something else that works. but it would be hard with something else.