So, I guess what I'm talking about is the long metal insert that runs all the way across the side of the rubber blade to hold it on the sliders.

If you look closely at my last picture where I compare the new vs old, the right hand side of my old blade sits flush with the end of my frame, whereas the left sticks out about an inch. The few times I had to use my windshield wiper, the rubber blades started to fall off because of this.