The 1/4" thickness with specially designed memory foam. Thick enough to protect your knees and joints, while still allowing you to grip the floor for balance. Indentations will disappear in time with use. * Durable and Long Lasting material/ SGS approved. Phthalates/Latex Free * Colors that Define your Inner Self/ Focal Point Icon to help concentration * Review photo instructions on how to prevent slipping with our Slip Free Rosin * Great Customer Service and all Products Guaranteed. Two Time Top Seller/Service Award Winner