That sucker is really tough at first. Take your time and work it slowly and it will come out. I was worried about breaking it at first but it comes out easier after the first few times. 1/4 turn does it. I don't take mine out unless I'm changing the backstraps and use a pen or something for the sear when field stripping. Keep at it. It'll come out...

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Why duck?? It's a 9mm!