I purchased 2 of these first had to return one i did ask for a replacement. I use it to take stickers off of car windshields. I used the first one and it just opened up, I used pliers to try to close the prongs that hold the blade in and nothing worked. I received the replacement and I just used it. And it has the same issue. Not as bad as the one I returned but again, try to put pressure to remove a sticker from a glass, the pressure makes the two parts come apart or separate.l and then you can't close them back. So there is no pressure to hold the blade in its place. I will need to return this one as well. I'm willing to give it one more try. But the mechanism that holds the blade needs to be looked at it is very poor quality.