I was expecting these mats to be durable and functional- they are neither. The mats are made of light foam, even a preschool has thicker and denser play mats. I intended to use these mats for working out, plyometrics, weightlifting, etc. However, not only do the mats easily slide and slip around, but they are prone to tearing. Also, each mat piece is 1 square foot, and even when they are pieced together, it is not hard for them to get out of place, posing as a significant trip hazard, especially if you are working with dumbells. Not to mention that there were not enough border pieces included so I had even, smooth sides. Nope. These mats are not gym-quality. I highly discourage purchasing these mats as they are extremely low quality, prone to get damaged easily, and possess an extreme level of risk because they are not well-constructed.