The 350713-4 are 5.0 mm Power Key Connectors for power circuits of home appliances, especially targeting gas appliances. The connector features four kinds of keying per housing. Only color-coding of housings limited the efficiency of blind mating where you could not see connectors. However, the new keying mechanism not only improves assembly efficiency but also helps prevent mismating. Part numbers involved can be reduced so that purchasing and stock level control can be made simpler.