[villagetinker]

Originally Posted by Vladimir

Villagetinker - you must have different sliders than I do. There is no gap for a block and the slider is flush with the top channel. The only way I could see that they could be lifted out of their tracks is by removing the screwed in bottom channel plates or by opening them past a certain point. I have placed dowels in the track to reinforce the weak lock mechanism

Vladimir,
You are probably correct, there appears to be a variety of components used in the houses over the years. You can try lifting the slider to see if it moves, if not then you are probably good. The Sumter county Sherriff offers a free security review if you are in Sumter county. I was under the impression that all of the sliders could be lifted out as this is the way they were installed, however, there could very well be a version that uses a different installation process. Be sure that the bad guys cannot reverse the installation process and get into your house.

Hope this helps.