I purchased a 9mm EZ Shield about a month ago. Nearly every time she tried to lock the slide in to open position, before inserting a magazine into the mag well, the slide stop would disengage allowing the slide to close. I attempted the same, with similar results. It appears that the slide stop does not fully engage the slide stop notch. In fact, the slide stop barely touches the notch, witch would cause the slide to release or close in the forward position. She refuses to use the EZ because it pinched the heal of her hand three times, twice drawing blood.
