Robust Bit-Check provides a quick overview of which tools are available for use. The bits that are not used are simply placed back in the holder and are never lost. Easy to carry, e.g. in a shirt pocket. Includes universal holder with stainless steel socket, snap ring and strong permanent magnet for fixing bits with a 1/4" hexagonal drive according to DIN ISO 1173-C 6.3. For mounting in a screwdriver or the chuck of an a electronically controlled drill. With torsion form to prevent premature wear. Tempered, for universal use.