Description: These extension holders are made with a high quality metal with heavy duty construction to ensure durability and efficiency. They are covered with anti-proof cover and the cover is separated from holder body so you can hold cover while using electric screwdrivers, in order to avoid waggle. They c an be used for a variety of drivers making these extension holders very handy. Features: Hard metal holder for durability, t he heavy-duty construction allows for long service life. Bit holders are designed to be extendable and can be lengthened with a simple pull. 1/4inch quick hex shank and 1/4inch hex socket fit most electric drivers, hand-held drivers and bits. The small size allows you to bring your bit extension anywhere to get any job done and c an fit into many tool bag. Very helpful to remove or tighten a large number of screws after you've started or loosened them. Specifications: Main Material: 08F iron, aluminum Hex Shank: 1/4" Hex Socket: 1/4" Retracted Length: 80mm(3.15"), 120mm(4.72") Extended Length: 120mm(4.72") , 200mm(7.87") Quantity: 2 Package Includes: 2 x Extension Holder