Connection: Product Name: XT60 parallel connector Connector Type: 1 female to 2 male No wire Connector. Size: 4 x 1.6 x 1.7cm Quantity: 5 Use for the RC Quadcopter power system , Also compatible with: other RC helicopter airplane boat car power system. Example: 2 PCS 3S 11.1V 2200mah batteries can be changed into 1 PCS 3S 11.1V 4400mah battery. Warning: When using this adapter, the 2 batteries should be the same capacity and the same voltage, or the batteries will produce internal friction between them. Package Content: 5* XT60 parallel connector