Impact-resistant plastic elbow and knee pad set with adjustable straps for a great fit. - Brand: OOTO - Type: Elbow and knee pad set - Color: Black and gray design - Size: Free size - Material: Impact-resistant plastic and nylon - Features: Adjustable straps - Uses: Inline skating, roller skating Thank you for viewing. While I don't personally see any stretching in the rubber or other materials, there is some fraying on the fabric on the back of both knees. I am selling these because my child has outgrown them, but I believe they are still wearable, so I hope someone can use them.