2.5mm male input,2.5mm female output. Suitable for Smartphone with 2.5mm port or 2.5mm earphone and 2.5mm male to male cable. Easy to use, plug and play 2.5mm female to male audio cable color:black Material: Plastic Suitable for any device with 2.5mm plug. Can not fit 3.5mm device. 2.5mm male to female plug 4 pole 3 ring extension Audion Aux Cable Cord Length: about 1.5m