Conspicuity marking tape often referred to as conspicuity tape or DOT reflective tape in the US, Conspicuity marking tape is a highly reflective adhesive tape designed to make vehicles, particularly large trucks and trailers, more visible, especially during nighttime and in low-light conditions.

The primary goal is to enhance the conspicuity (visibility) of vehicles to other drivers. By outlining the sides and rear of large vehicles, it helps prevent accidents, particularly side and rear-end collisions when visibility is poor.

It uses retroreflective materials, often microprismatic technology or glass beads. This means it reflects light directly back towards the light source (like headlights) with minimal scattering, making the tape appear very bright to the driver of the illuminating vehicle.

Conspicuity reflective marking tape  most commonly seen on heavy-duty trucks and trailers, it's also used on:
Buses
Emergency vehicles (police cars, fire trucks, ambulances)
Agricultural equipment
Construction vehicles
Sometimes even bicycles or personal vehicles for added safety.
Many countries and regions have specific regulations mandating the use of conspicuity tape on certain vehicles.

In the United States the Department of Transportation (DOT) requires trucks and trailers meeting specific size and weight criteria to have DOT-C2 compliant tape applied in specific patterns (alternating red and white blocks) on the sides and rear.

In Europe similar regulations exist under ECE R104, specifying requirements for reflective markings.
Other regions often have comparable standards. These regulations typically dictate the tape's color, reflectivity levels, durability, width, and placement pattern.

The most common configuration, especially for regulatory compliance on trucks, is alternating blocks of red and white. Solid white conspicuity reflective marking tape and solid red conspicuity reflective marking tape are also used. Yellow is sometimes used, particularly on school buses or construction equipment.

Conspicuity reflective marking tape significantly reduces the risk of accidents by making large vehicles easier to see from a distance and judge their size/shape.
Conspicuity reflective marking tape ensures vehicles meet legal safety requirements.