Vehicles are fitted with wireless Side Units and Cab Units. Together, they form a sensing system that allows the driver to know that a bicycle is near. Side sensors are permanently attached to the vehicle sides, two to four per side depending on length. They are spaces approximately 3 – 5 metres, with pairs of side units mounted near the front and back. Side units are ultrasonically welded to ensure a permanent, weather-proof seal, and have an expected battery life of up to 10 years. There is no wiring required.