White polyester water-blocking tape is a type of cable tape that is designed to prevent the ingress of water and moisture into a cable. The tape is made from a non-woven polyester material and is impregnated with a water-blocking compound, which swells when it comes into contact with water to form a barrier that prevents further water ingress. White polyester water-blocking tape is commonly used in power and communication cables to protect the cable from water damage and maintain the integrity of the cable’s insulation.