a suitable pen, such as a cheap ballpoint pen
a florist's water vial. I asked for a few of these at my local flower shop and she sold them to me for 25 cents a piece. Try to find thin ones as they will be easier to find heat shrink tubing to fit.
heat shrink tubing that will fit around the circumference of the tube. In my case I needed some at least 3/4" wide.
a heat source such as a propane torch or a heat gun or hair dryer