Features: 1.Stable Connection: These Bit Extension Rods Have Standard 6.35Mm Hex Socket Design, Ensuring Stable And Reliable Connection And Preventing Detachment And Loosening During Use. 2.Chromium Vanadium Steel: The Extension Bit Holder Is Forged With Chromium Vanadium Steel, Which Has High Hardness, Rust And Aging Resistance, No Deformation, And Long Service Life. 3.Buckle Fixing Design: These Hex Socket Bit Extension Rods Are Designed With Buckle, Which Can Fix The Drill Bit In Place And Facilitate Quick Disassembly And Replacement Of The Drill Bit. 4.Applicable Tools: The Bit Extension Rod Is Suitable For Conversion Purposes Such As Nut, Drill Bit, Pneumatic Driver, Electric Driver, Pneumatic Drill, Manual Driver, Etc., Has Strong Practicality. 5.Specifications: This Kit Includes 6 Different Lengths Of Bit Extension Rods, With 60Mm, 100Mm, 150Mm, 200Mm, 250Mm, And 300Mm Specifications, Suitable For More Usage Scenarios. Specification Item Type: Bit Extension Rod Material: Chrome Vanadium Steel Special Design: Self Locking Buckle, Strong Magnet Connector Size: Approx. 1/4In (6.35Mm) Specification: Approx. 60Mm / 2.4In, 100Mm / 3.9In, 150Mm / 5.9In, 200Mm / 7.9In, 250Mm / 9.8In, 300Mm / 11.8In