Engineered for narrow trench applications up to 5' in depth, the 4"- diameter ball marker has a unique, patented self-leveling feature that ensures an accurate, horizontal position regardless of how it is placed in the ground.

The main element of the 3M Electronic Marker System (EMS) is a durable, passive marker that can be buried over key facilities during construction or used to mark existing facilities during maintenance.

The full-range marker is suited for deep applications up to 8'. Its 15" diameter makes it ideal for use as a digging shield over sensitive underground facilities.

Designed for marking applications up to 6' in depth, marker spokes in the 8.5"-diameter mini-marker help stabilize it in the correct position after placement.

The near-surface marker is ideal for marking underground and street-access facilities up to 2' in depth. Its 3.5" length, cylindrical size and shape allows for easy installation in asphalt, concrete or rock without extensive digging or drilling.