If you can post some pictures we can advise with some more specific advice.
I am based in Central Florida and I run into these in the older homes and some of the mobile homes have them on porches. There are a few types, some with 7.5cm vertical height slats typically found on doors or bathrooms, some with 25-30cm vertical height slats found on standard wall windows. Also I have run into a few with full metal frames and rubber gaskets while others have glass to glass contact along the horizontal edge.