A milling tool for slot milling comprising - a tool body defining a rotation axis (C 1), - a plurality of first seats, which are separated in a circumferential direction, form root insert seats, and are arranged one after the other in the tool body along a first line (L 1) that extends around the rotation axis (C 1), - a plurality of flank insert seats separated in the circumferential direction, the flank insert seats comprising a plurality of second seats, which are arranged one after the other along a second line (L 2) that extends around the rotation axis (C 1) on a primary side of the root insert seats, and a plurality of third seats, which are arranged one after the other along a third line (L 3) that extends around the rotation axis (C 1) on a secondary side of the root insert seats, each flank insert seat comprising a bottom surface, an inner side surface, and an outer side surface, each root insert seat comprising a replaceable root insert, each flank insert seat comprising a replaceable flank insert, each root insert comprising an under side, an opposite upper side forming a rake face, a circumferential edge side connecting the upper side and the under side, and at least one primary main cutting edge and a secondary main cutting edge, which converge toward each other and are formed where the edge side meets the upper side, wherein a transverse end cutting edge extends between the primary main cutting edge and the secondary main cutting edge, each flank insert comprising an under side, an opposite upper side, and a circumferential edge side connecting the upper side and the under side, each flank insert defining a centre axis that extends through the upper side and under side of the flank insert, and the edge side of the flank insert forms a rake face, the rake face of the root insert extending in an extension plane (P 1) comprising the primary main cutting edge, the secondary main cutting edge and the transverse end cutting edge, characterized in that extension plane (P 1) has a normal that is parallel to a tangent of the first line (L 1) where the same intersects the extension plane (P 1) and the normal forms an acute clearance angle (α) with the edge side at least in the vicinity of said cutting edges (36, 37, 38) of the root insert so that the root insert itself possesses a positive geometry. - a tool body defining a rotation axis (C 1), - a plurality of first seats, which are separated in a circumferential direction, form root insert seats, and are arranged one after the other in the tool body along a first line (L 1) that extends around the rotation axis (C 1), - a plurality of flank insert seats separated in the circumferential direction, the flank insert seats comprising a plurality of second seats, which are arranged one after the other along a second line (L 2) that extends around the rotation axis (C 1) on a primary side of the root insert seats, and a plurality of third seats, which are arranged one after the other along a third line (L 3) that extends around the rotation axis (C 1) on a secondary side of the root insert seats, each flank insert seat comprising a bottom surface, an inner side surface, and an outer side surface, each root insert seat comprising a replaceable root insert, each flank insert seat comprising a replaceable flank insert, each root insert comprising an under side, an opposite upper side forming a rake face, a circumferential edge side connecting the upper side and the under side, and at least one primary main cutting edge and a secondary main cutting edge, which converge toward each other and are formed where the edge side meets the upper side, wherein a transverse end cutting edge extends between the primary main cutting edge and the secondary main cutting edge,