A 7 Blade connector is typically used with large trailers (RV and industrial) and is the most popular tow connector on new tow vehicles. This connector provides the following functions left/right turn, taillight, ground, auxiliary, electric brake and reverse. End socket7-pole connectors are typically used with large trailers, RV, and industrialProvide all the function of the 6-pole with the addition of the backup reverse functionRound designPlastic construction