A tool body assembly for use in a tool assembly configured for chip-removing machining of a workpiece, the tool body assembly comprising: - a drilling tool body having a front end and a rear end between which a centre axis and a peripheral envelope surface extend, wherein at least one peripheral insert seat for mounting of a peripheral cutting insert and at least one centre insert seat for mounting of a centre cutting insert are provided in the front end, - a coupling member having a first end configured for engagement with the rear end of the drilling tool body, and a second end configured to be fastened to a holder of a machine, wherein the rear end of the drilling tool body comprises a male engagement member extending along the centre axis, and wherein the first end of the coupling member comprises a female engagement member configured to receive the male engagement member of the drilling tool body, - at least one securing member configured to prevent axial motion of the drilling tool body with respect to the coupling member, and - torque transfer means configured to transmit torque between the coupling member and the drilling tool body, characterised in that the torque transfer means are positioned to allow fastening of the drilling tool body to the coupling member in one of totally two available rotational positions separated by 180°, in that a protruding flange is formed between the male engagement member and the front end of the drilling tool body, and in that the securing member is an annular securing member configured to be mounted around the flange of the drilling tool body and be securely engaged with the first end of the coupling member when the male engagement member is received in the female engagement member. - a drilling tool body having a front end and a rear end between which a centre axis and a peripheral envelope surface extend, wherein at least one peripheral insert seat for mounting of a peripheral cutting insert and at least one centre insert seat for mounting of a centre cutting insert are provided in the front end, - a coupling member having a first end configured for engagement with the rear end of the drilling tool body, and a second end configured to be fastened to a holder of a machine, wherein the rear end of the drilling tool body comprises a male engagement member extending along the centre axis, and wherein the first end of the coupling member comprises a female engagement member configured to receive the male engagement member of the drilling tool body, - at least one securing member configured to prevent axial motion of the drilling tool body with respect to the coupling member, and - torque transfer means configured to transmit torque between the coupling member and the drilling tool body, the torque transfer means are positioned to allow fastening of the drilling tool body to the coupling member in one of totally two available rotational positions separated by 180°, in that a protruding flange is formed between the male engagement member and the front end of the drilling tool body, and in that the securing member is an annular securing member configured to be mounted around the flange of the drilling tool body and be securely engaged with the first end of the coupling member when the male engagement member is received in the female engagement member.