Oneway Stronghold Chuck #4 Jaws, Smooth are the largest capacity smooth jaws ed by Oneway, designed to provide the mass and size necessary for turning large bowls and vases with ease. These jaws are specifically for use with round stock only, ensuring optimal performance and precision. The external (compression) chucking capacity ranges from 4-1/4" to 5-3/8", while the internal (expansion) capacity extends from 5" to 6-1/2". This makes them i for woodturners seeking reliable and robust jaws for their projects. Model Number: 3221