Adaptors A comprehensive range of screwdriver bit holders, extensions, adaptors and angle attachments designed for the construction and associated industries, tradesman and diy enthusiast. SCREWDRIVER BIT HOLDERSA screwdriver bit holder is an accessory that can make driving screws with power tools a quicker and easier process. In most cases they are an essential item when working with the short 25mm bits as they are not usually suitable for direct fitting into a hex chuck on impact drivers and electric screwdrivers.• Magnetic Bit Holders - On a basic magnetic bit holder, 1/4" hex bits are held in place purely by magnetic force. The advantage is that bits can simply be pulled out when they need to be changed over, but they can also detach from the bit holder if they become stuck in the screw head or workpiece.• Quick Release Bit Holders – usually combined with a magnet, these bit holders have a locking collar which grips the bit securely and ensures they can't fall out during use. The collar is simply pulled down or pushed forward to release the accessories. These are ideal for use with longer accessories and helps keep frustration to a minimum during more intensive applications.• Impact Bit Holders - these are designed to withstand the extra stress generated by impact drivers, if you need a bit holder for an impact driver you should select one that is impact rated for durability.