This unique device enables accurate fixing in overhead or awkward positions without the necessity of pre-drilling. The in-built spring also allows for countersinking. These bits are German made and of premium quality. The surface of the screw head is held on by an additional ultra strong, powerful, rare earth magnet allowing for vertical or horizontal screwing without slippage. Allows precision screwing with a single hand operation, saving time. Suitable for use with all 25mm 1/4" driver bits. The bits retract within the mechanism allowing the screw to magnetically attach to the end of the holder.