The Wera 897/4 IMP R Impaktor holder with retaining Ring Magnet for secure holding of screws up to 10in. 

Impaktor holder to cushion extreme impulse peaks, special torsion effect from the double-torsion spring, equipped with a ring magnet to easily hold longer and heavier screws, also ideal for above-head work, particularly suitable for use with impact drivers, the magnet can be retracted and in this way be disabled
Output: Suitable for bits with 1/4in hexagon head drive as per DIN 3126-C 6.3 and Wera Series 1
Design: Impaktor technology ensures an above-average service life even under extreme conditions thanks to a best possible utilisation of the material properties and optimally designed geometry (two coupled torsion zones that perform successively), fitted with retaining ring and magnet
Drive: 1/4in hexagon, suitable for power driven screwdrivers with DIN 3126-F 6.3, ISO 1173 chucks