Protects medium pile carpets up to 3/4-inch thick including padding. Exclusive Anchor Bar chair mat cleats hold firmly in place yet are gentle on carpet and fingers. Crystal Edge creates a smooth finished edge of superb clarity while providing effortless roll on/off mat. Protects against wear and tear from chair casters. Engineered for optimum clarity, high performance and a smooth effortless roll. Made in the USA. "No Crack Mat" Guarantee. Crystal Edge creates a smooth finished edge of superb clarity while providing effortless roll on/off mat. Chair casters dig deep into carpet restricting chair movement while quickly causing damage to your floor.