The Celsius Deluxe Fitness Mat features a durable 10mm Nitrile rubber (NBR) construction offering consistent support and training protection. NBR is a manmade rubber that produces a thick, extremely comfortable and well-padded mat, which makes it a favourite for yoga enthusiasts. In addition, NBR is sweat and water resistant, making the Celsius Deluxe Fitness Mat ideal for stretching and doing floor exercises in great comfort.