Otherwise known in my studio as "death tape", this flexible, spicy, sharp material will save you so much time and energy in closing up your upholstery projects. It looks really fucking hard and intimidating to use, but I promise you it is not.
Once you get the hang of it you can use it to really step outside the box on how you choose to cover up your staple work. It's extremely satisfying to use once you master it, and looks like a goddamn magic trick every time you show someone how it is done. It WILL make you look cool at parties. Trust.
It's a sonofabitch to store and use without minor injury, but I hear a pizza box makes it a bunch easier. Just cut a hole in the middle and feed it out. 6 years, and I still store it in a knot under my toolbox...