Abstract: A hole saw having a cylindrical configuration and having hard particles disposed on both ends thereof, and a clamping surface between the ends for fixing in a drill chuck.

Abstract: A tool set having a screwdriver handle with a chuck for insertion and latched mounting of screwing-tool inserts provided with standard polygonal shank segments, and having screwing-tool inserts, which are insertable into the chuck and are provided with the standard polygonal shank segments, in particular bits, nuts or ratchets and extensions for drive of the latter, comprising a supplementary tool which has a plier head (2) and a plier-handle projection (4) which is disposed immediately behind a knuckle joint (5) and is in form of the standard shank segment of the screwing-tool inserts, the screwdriver handle (9) latches to the plier-handle projection by its chuck (10), forming one of two plier arms and a blade extension (11) which likewise has a chuck (10), forming other of the two plier arms.