Premium Material: Twist Socket Tool Kit is crafted from high hardness chrome molybdenum steel, this extractor set is designed to withstand heavy use and provide long term performanceEngineered Extractors: Each bolt extractor in the set is engineered to effortlessly remove stripped, rusted, or bolts, nuts, and screw with easeComprehensive Set for Versatile Use: This 13 pieces bolt nut extractor tools set includes a variety of extractors suitable for different sizes and types of fasteners, making it an essential addition to any toolboxCompact Packaging for Easy Storage: The entire set comes neatly packaged in a compact box measuring 21.7 cmx14 cmx4 cm/8.54 inchx5.51 inchx1.57 inch, ensuring easy storage and portabilityComplete Package Contents: The package includes 13pcs Bolt and Nut Remover set of screw extractors, providing you with all the tools needed to tackle stubborn fasteners effectively Specification: Material: Chrome molybdenum steel Includes: 1/4 , 5/16' 8MM , 3/8 , 10MM , 7/16 11MM , 12MM , 1/2 , 13MM , 9/16' 14MM , 5/8 16MM , 17MM , 11/16 , 3/419MM Size Chart: Packing size: 21.7 cmx14 cmx4 cm/8.54 inchx5.51 inchx1.57 inch Package Includes: 13pcs Bolt Nut Remover Set Note: Please allow slightly errors 1-2cm/0.39-0.79inch differences due to manual measurement.