My battery needed replacement because the battery had swollen and was warping the glass. Looking at it from the side it looks like gasket that was partly sticking to glass and partly to the case. This is actually part of the glass frame and you need to make sure to separate it from the case not the glass. I did it wrong and ended up removing the glass but there was a metal case covering the inside. I eventually got the rest of the top off but now I'll have replace it all because I can't find a good way to glue the glass to plastic.