It sounds like you are looking for two different parts so I have listed both kinds of 7-way connectors below.
Trailer Side 7-Way Connector no cable - Pollak Black Plastic 7-Pole, RV-Style Trailer Connector item # PK12706
Vehicle Side 7-Way Connector receiving part that is built into hitch - Pollak Black Plastic, 7-Pole, RV Blade-Style Trailer Socket item # PK12-707E
I have linked a couple of installation videos below. Feel free to email me back with any additional questions. view full answer...