DynaRound Warning Lines are designed to eliminate the risk of falls by creating a roof top safe zone. There are two options available: Heavy-Duty (HD) Warning Lines and Light Duty (LD) Warning Lines. The HD Warning Line system is a permanent warning system with heavy-duty base plates, plastic coated cable and your choice of plastic or metal pennants. The LD Warning Lines are generally used for temporary applications and features folding stanchions with a nylon line and vinyl flags that can be set up quickly.