1.Alloy Steel Materials: Crafted from premium alloy steel, both the drill bits and screw extractors are built to last. The materials ensure that these tools can withstand heavy use and provide consistent performance over time. 2.Complete Tool Set for Every Need: This 10pcs set includes 5pcs left hand drill bits and 5pcs alloy steel screw extractors, providing a comprehensive solution for various drilling and extraction tasks. 3.Convenient Metal Case: The left hand drill bit set comes with a sturdy metal case that keeps them organized and protected. The case is compact and easy to carry, making it ideal for professionals and DIY enthusiasts who need to transport their tools to different job sites. 4.Effortless Broken Bolt Removal: The screw extractors are specifically designed to remove broken or damaged bolts, screws, and fittings with ease, making them a musthave for any mechanical repair or maintenance task.