I felt that the method by which they were shipped was very poor. They were warped and bent out of shape. It took some time just to get them reasonably flat. Previous shipments where much better
Didn't like the softness of the plastic. Used on rug wheels from chair would sink in a bit leaving an indentation. Also not very easy for chair to slide over possibly because lack of hardness in plastic. Maybe best used on industrial type rug or carpet.