(Sept 5: Apologies for that last photo, it was truly awful. I've replaced it, this one is better but I don't rate myself as a photographer.)
I've tried so often to attach a pen or pencil to a sketchbook, usually with masking tape. Masking tape doesn't last for long and it leaves a sticky residue just where one holds the pencil. So I was delighted to stumble on this in the office shop. It's a simple and effective idea. The spiral binder is covered by canvas which is stitched onto the front and back covers, and the pen-holder loop is stitched into the front seam. It works for any pen which has a clip such as Micron pens (can't find one right now for the photo). Really neat and duly snapped up.