I purchased these from a store. I do not recommend them for transporting files. They're too lightweight and the latches are too weak to safely carry a heavy load. But they serve my purpose well which is to store light seasonal clothing items like scarves and gloves at the back of a closet shelf easily visible through the clear plastic.
I've bought containers like this before. These containers are good but the lid doesn't latch tight. I've had times when it doesn't latch at all so stuff ended up falling out of the containers. I hope they will work for my purpose of transporting supplies to and from meetings.