Fills its purpose for sliding window and door security. Our house had windows and doors from the 80s with thin frames and shoddy locks (original and aftermarket type). I wanted something more significant that wasn't a wonky hack. I got some of these bars and cut them down to size to allow secure venting. I plasti-dipped them to stop the rust and put some 550 cord around them in loops to aid in lifting. I know it's overkill, but I find 2x4s tacky in this application and the metal bars fit snugly in the tracks, looking very sleek. Now I know that crooks would certainly have to break the windows or doors to gain entry. I'm sure if your project calls for sturdy, heavy dimensional steel bars, these should work for you too! These aren't stainless so prepare to deal with oxidation somehow.