Anti-Curl System - 4 Piece Set Keeps Carpet and Rug Corners or Edges Flat - Safe for Hardwood Floors Works better than carpet tape to help prevent trips and falls Four corner anchors - Each is 4 x 4 inches and super-thin - only 0.5mm thick Adhesive pads sticks to the rug or mat, not your floor; installs in seconds and easy to remove Safe for all floor types and can be used with non-slip rug grippers or mats for extra safety Use indoors or outdoors, including kitchen or bathroom - Does not prevent sliding or crawling