This is a cord that splits in two, allowing you to connect two Gerbing's products to one battery harness. Ideal if you want to heat your jacket or vest and socks or insoles at the same time. However, you will not be able to select different temperatures for the separate areas being heated. Therefore, we advise you to buy the dual portable or dual permanent temperature controller if you would like to heat two products separately. The temperature controller allows you to adjust the temperature of your Gerbing's heated clothing while driving.