Elderlee, Inc. 9024.11005 Stop Sign, MUTCD R1-1 .100 Aluminum, 24 x 24 Inch, 3M High Intensity Reflective Sheeting, 5-Pack Heavy gauge .100 aluminum for superior durability and rust free protection Durable 3M high intensity reflective sheeting material, fade and UV resistant Signs are pre-drilled for easy mounting to a wide variety of posts or surfaces Vivid colors provide 24 hour performance in various traffic situations Meets Federal MUTCD (Manual on Uniform Traffic Control Devices) sign standards and specifications. Consult applicable agencies to ensure compliance.