OK, I'll try to explain it again and see if I can make it clearer this time.
My parka is made of two separate layers, one of canvas the other of Ventile.
These layers are connected together at the edge of the hood with Velcro which means that there is a catchy strip on one layer and a loopy strip on the other to hold the two shells of the hood together.
The fur of my ruff is glued to a wide strip of canvas so that there is a 3/4 inch strip sticking out all along one edge. To this edge I have stitched Velcro to both sides with the catchy strip on one side and the loopy strip on the other.
To fit the ruff to the parka, all I have to do is split the two layers of the hood, place the Velcro strips of the ruff between the appropriate strips on the hood and squeeze them back together.
I hope that makes more sense.