Define "but ass Philips head screwdriver". You could do this #2 screws which are tiny, use 3-6 of them around the edge. Add a rubber gasket. And you have a wat

Define "but ass Philips head screwdriver". You could do this #2 screws which are tiny, use 3-6 of them around the edge. Add a rubber gasket. And you have a water proof battery that is replaceable in under 5 minutes with a precision Philips head (aka those little screwdriver heads you get with the multi-head screwdriver kits)