Description: 1. Serial port hole through the hole: 1-1 2-2 3-3 4-4 5-5 6-6 7-7 8-8 9-9 2. Male to Male 3. Polyethylene HDPE insulation, anti-interference, transmission signal attenuation less, the use of good results. 4. Uses the UL standard design, applies the connection between the computer and the serial port equipment and transmits the signal between them Package Included 1 X Male to Male DB9 Expention Cable.