A extension patch cable would be defined as a patch cable that is female at one end and male at the other. It is not recommended that you make your own. The reason for this is that male end terminations require the use of stranded cable and female end terminations require the use of solid core cable. So no matter what kind of cable you use it will cause problems and have poor signal transmission. It is recommended that you use a one appropriate length cable in stead of two shorter cables connected together. Or use a factory made extension patch cable the is designed to be used in this way.