I want to make a jewelry pouch for my DIL. It will have a drawstring. I want the drawstring to remain tight after pulling and I would like to use a "thingy" I have seen on other drawstring items that works like this: The "thingy" looks like a good size plastic bead and both ends of the drawstring are threaded through it. It has a little button that can be pushed, which releases tension on the drawstring so that it can be pulled tighter or loosened. I've looked at Joann's website for drawstring and closure, but don't see anything even close. What would I even search for?