Maypole bike rack lighting board wiring kit 12n 18m snap connector cycle cycle board wiring kit designed for vehicles with no tow bar kit contains relay and wiring to allow cycle lighting board to be fitted relay audible sensor cable 18m with a 12n flying socket snap connectors included the 7 pin n type 12n trailer plug is used for supplying all trailer lighting excluding reverse this is the most popular plug and socket used on trailers and caravans in the uk and europe full