Delineators are used as guidance devices to help road users identify the alignment of the roadway. Rather than warning devices, delineators are considered guidance devices useful at night and in harsh weather conditions. Delineators should be installed in a series. Because of these reasons, MUTCD Section 3D.03 specifies that delineators shall match the color of the adjacent edge line. On the other hand, object markers are used to mark obstructions within or adjacent to the roadway. Type 1 and Type 3 object markers are used to mark obstructions within the roadway and Type 2 and Type 3 object markers are used to mark obstructions adjacent to the roadway.