Feature:1. SPECIFICATIONS: 1 or 4in hex shank screwdriver bit holder, including 5 socket extension bars of different colors and metal keyring, convenient and practical.2. GOOD COMPATIBILITY: Compatible with most 1 or 4 quick hex handle and 1 or 4 hex socket, as well as various electric screwdrivers, hand screwdriver and drill bit.3. METAL MATERIAL: The extension bit holder is made of excellent metal, the chrome plated surface is rustproof, corrosion resistant and oxidation resistant.4. WITH KEYRINGS: Each socket is provided with a keyring, and hung on a keyring to prevent it from falling, which is helpful for high altitude operation.5. PORTABLE DESIGN: The keyring screwdriver bit holder is portable design, and the socket surface is knurling texture design, which is non slip and durable.Specification:Item Type: Hex Shank Bit Holder Inner Diameter: 1 or 4in (6.35mm)Socket Extension Bar Length: Approx. 3.4mm or 0.13inSocket Extension Bar Outer Diameter: Approx. 1.6mm or 0.06inKeyring Diameter: Approx. 25mm or 1inSpecification: Keyring, Red, Yellow, Blue, Green and Black Sockets(Grid Pattern Knurling).Package List:1 x Bit Holder (With Keyring, Red, Yellow, Blue, Green and Black Sockets)