SWEATY BETTY London Eco Yoga Mat Charcoal SB 4023. You are purchasing a Brand New SWEATY BETTY London Eco Yoga Mat Charcoal SB 4023. This mat has 5 mm thickness. It has different patterns on each side. The top side has a high grip. The bottom side has a mid grip. It has a membrane to keep shape. It is made of TPE (Thermo Plastic Elastomer). Please feel free to ask questions prior to purchasing. This is a hard to find mat.