groove 15 is recessed into the bit shank bit shank 11 is attached via a centering segment 12 to a bit head 13 bit head 13 comprises at its end facing away from bit shank 11 a bit tip 14 made of hard material for example hard metal a cup into which bit tip 14 is soldered is recessed for this purpose into the end of bit head 13 as is evident from fig1 bit head 13 possesses a collar 13 2 in the attachment region to centering segment 12 collar 13 2 constitutes a downwardly directed contact surface 13 1 bit 10 is embodied with its bit shank 11 its bit head 13 and its bit tip 14 rotationally symmetrically with respect to the longitudinal center axis extending through bit tip 14 a mounting sleeve 20 is arranged in the region of bit shank 11 mounting sleeve 20 is produced from a planar material for example sheet steel holding elements 21 are stamped out of the planar material and pushed out into the region surrounded by mounting sleeve 20 holding elements 21 are cut out along two stamping edges that extend in a circumferential direction of mounting sleeve 20 mounting sleeve 20 is rolled up in such a way that a circular cross section results leaving a clamping slot 23 a support element 30 is slid onto mounting sleeve 20 support element 30 is of disk shaped configuration the conformation of support element 30 will be explained in further detail below with reference to fig3 as this drawing shows support element 30 comprises on its side facing toward the bit head a cup shaped recess 31 into which bit head 13 can be set with its collar 13 2 in that context bit head 13 rests in planar fashion.