Erbauer Aluminium Alloy Screw Guide is ideal for a range of domestic and trade applications Screw Guide is compatible with the ¼" hex bits models Hex head for quick changing of driver bits Retractable sleeve helps hold screw in place while driving Magnetic tip of Erbauer Aluminium Alloy Screw Guide holds screw to driver bit Screw Guide is made of aluminium alloy Shank type: Hex; Standard: DIN 3126