Specifications include, but are not limited to: piezoelectric traffic sensor designed for permanent installation into or onto the road surface for the collection of vehicle classification data. These sensors will be flexible to conform to the profile of the road. They will produce minimal road noise due to road bending, adjacent lanes, and bow waves of approaching vehicles. They shall have a small profile to reduce damage of the road surface and the amount of grout used for the installation. The sensor will be capable of classifying vehicles into the 13 categories as described in FHWA Scheme F. These sensors must be compatible with the EMU3continuous traffic counters manufactured by TDC.Signal•A positive signal shall be produced as tires pass over the sensor•Functions for a dynamic range – from small to large vehicles•Produces high capacitance to drive the signal over long cables•Works for slow to high speed vehicles