3Pcs 1/4 Hex Shank Quick Release Magnetic Screwdriver Extension Holder Drill Bit Product Feature: High quality: quick release bit holder made of industrial heavy-duty chrome vanadium steel(CR-V) for maximum durability and long life. One-piece construction for the best concentration of force and a longer lifetime. Stong magnetism: magnetic drill extension bit holder is featured with stong built-in magnetism which makes sure screwdriver bits stay in place and a quick release collar which allows for easy 1-handed bit tip changes. Wide applications: The drill bit extender set is designed with a 1/4" hex shank and a 1/4" extension chuck adapter. Fit for all inserts and 1/4 in. hex bits. The quick-release magnetic drill bit extension is great for extending all kinds of screwdriver bits, drills, nuts, batch heads, pneumatic screwdrivers, electric screwdrivers, pneumatic drills, manual screwdrivers, and impact drivers. What you get: 3 pcs drill bit extension set with built-in magnetism in three sizes. 3 sizes included： 2"(60mm), 4"(100)mm, 6"(150mm) to satisfy your various needs. Product Specification: Type: Magnetic Screwdriver Extension Drill Bit Quantity: 3Pcs Material: Chrome vanadium steel Size: 2"(60mm), 4"(100)mm, 6"(150mm) Color: Red+Black Shank Diameter: 1/4" Hex Shank Features: quick release, built-in magnetism, multifunction Fit for: 1/4" hex shank and a 1/4" extension chuck adapter Application: screwdriver bits, drills, nuts, batch heads, pneumatic screwdrivers,electric screwdrivers, pneumatic drills, manual screwdrivers, and impact drivers Package Included: 3 x Magnetic Screwdriver Extension Drill Bit