1. Multiple Sizes in One Set: 13 pieces 3/8 inch drive bolt and nut remover set with easy-to-read markings: 6.35mm (1/4'), 8mm (5/16'), 9.5mm (3/8'), 10mm, 11mm (7/16'), 12mm, 12.7mm (1/2'), 13mm, 14mm (9/16'), 16mm (5/8'), 17mm, 17.5mm (11/16'), 19mm (3/4'). It can meet most of your needs for removing various stripped bolts and damaged nuts. 2.: Made of high-quality high-carbon steel material, hexagonal spiral design, high hardness, not easy to slip, high temperature quenching, not easy to break. 3. Wide range of uses: The special internal thread design is precision-engineered to easily remove damaged bolts, nuts and screws in household appliances, automotive repairs and industrial instruments, even if they are stripped, rusted or frozen. 4.6-Point Spiral Grip: Each section of this socket set for removing stubborn nuts has six grip points and an internal spiral design to provide maximum grip and torque as you pry off damaged, corroded and coated nuts, bolts, nuts, studs, hex screws, etc. 5.3/8' Drive: Our nut and bolt extraction tools easily pry off rusted, stripped and frozen fasteners and can be used with hand and power tools with a 3/8-inch drive, including impact wrenches, pneumatic ratchets and breaker bars