Filling file teeth with this chalk is an age old "Gunsmith Kink"® to prevent "pinning", the buildup of metal chips in the teeth of the file. It increases the effectiveness of the file, extends file life, and produces a smoother, more professional finish. Metal removal is faster and easier, too. An inexpensive time and money saver. For superior results, use file chalk along with a good file card, listed elsewhere. Mfg: Brownells SPECS: 4" (10.2cm) long, 1" (2.5cm) diameter 2 pieces per tube.