Swanson® 6 in. Marking whiskers are the best alternative marking choice for survey and construction sites, underground utility locating, and more. These marking whiskers are virtually indestructible and are designed with a flexible PVC that will spring back up when run over by equipment. They easily and conveniently attach to wood stakes or fasteners. Use them alone or in conjunction with other marking products. Swanson® marking whiskers are ideal for marking grades on construction sites, athletic fields, property boundaries, forest trees for harvest, cemetery plots, landscaping/irrigation, and underground utilities.