... strength 2.bright color 3.high quality with low price underground aluminium foil detectable warning tape 1) Made from thin ... (PE/ AL FOIL/ BOPP), serves as protection for the underground pipe protection, such as water pipes, gas pipes and oil ... bright colors, which help strengthen the visual results3) Designed for underground pipe protection4) Specification for each roll: Common Thicknesses: 4mil,4 ...