Mark buried utilities quickly and easily with these marker balls and disks. Passive electronic markers provide a unique electronic signature when activated by all types of EMS locators. Unlike surface markers such as stakes, flags or paint, these markers won't be inadvertently moved or worn away by weather.
3M EMS Full-Range Markers are uni-directional disks, meaning you have to be nearly directly over the marker to read. Their flat design is perfect for attachment to non-metallic utility box lids and other buried enclosures. Disks measure 15" in diameter, and include a mounting bracket.