This set of precision-ground, high-grade collet steel 5C collets, is designed to provide maximum accuracy and performance for your machine tool projects. The set includes 15 different sizes, 1/8", 3/16", 1/4", 5/16", 3/8", 7/16", 1/2", 9/16", 5/8", 11/16", 3/4", 13/16", 7/8", 15/16" and 1". The 5C collets are known for their versatility and ability to hold a wide range of round shanks and are compatible with 5/8" or 0.625 inches spindle. These collets are made from high-grade collet steel and precision ground to exact tolerances, ensuring the highest precision and accuracy. Whether you're a professional machinist or a hobbyist, this set is a must-have for any machine tool project.