Here is a link to the Jennoop, and a link to a Youtube video that demonstrates it:
http://www.jennoop.com/suspenders.html
https://www.youtube.com/watch?v=gJGph8am6BE
If you do a search on the QB, you will find some threads that talk about it. Every post I have seen from someone who has used it has been positive. Some people have made their own with PVC.