This is a full mains filter build that can be made with or without the chokes if you wish. The first picture shows the unit I made in a simple ABS case. This filter is a complete DIY solution where you make the circuit yourself, either on a PCB, vero-board or tag strip.
The sonic benefits of any mains filter is subjective at the best of times. Some people swear by them and others dislike them. I have always preferred my system with some kind of filtering and cannot see the purpose of using high grade audio mains leads without a filter circuit before them. The filter isolates the audio grade mains lead from the yards of twin and earth grey cable under the plaster and the miles of cable to the local sub station on your phase.