The Yellow Perimeter Warning Line Pennant Set by Tie Down Engineering includes a caution stencil on the warning line yellow flags, reading, "Danger Men Working." This Perimeter Warning Line Pennant Set complies with OSHA 1926.501(b)(1) and was designed for the Tie Down Galvanized Warning Line System. But, this product also works with any perimeter warning line system! This warning line flag set includes a 60 ft. high-strength rope with yellow vinyl safety pennant flags. The durable warning lines are easy to use and quick to set up. Tie Down Engineering maintains high standards and quality control through quality raw materials and components made in the USA.