Knot used to tie draperies on bar

[sp010123]

Someone taught me a knot that can be untied with one single pull but also strong...but I forgot it!!! (Have been away from draperies for too long while spending my time with wrenches and cables..)

Anyone can tell me what is it or suggest a good one?

 

[Van]

I like to tie on by making a full wrap with one side of the ribbon. Then, back on top of the pipe, tie a Bow knot with only one loop sticking out. When the tail to the loop is pulled the whole knot thing just pulls right off.
When doing "Opera Ties" you do the same thing only on the back of the pipe instead of the top.