4″ Ultra Precision Toolmaker’s Vise ~ Hardened and precision ground, HRC55~60°. ~ The “no-rise” jaw construction exerts a continual downward pressure to the jaw, eliminating tilting & lifting. ~ Jaw can be opened and closed without unbolting the vise from the work surface. ~ Tolerance is within .00012″(Parallelism) and .0002″ (Squareness). ~ Jaw width is 100mm/3.94″.