To provide a throw-away tip capable of favorably handling wide-width and thin cutting chips in an undercut turning.

This throw-away tip used for a profile turning is so formed that a chip breaker projection erecting upward from a rake face 21 includes a first breaker projection 30 extending along a bisector B of a corner cutting edge 22a, a second breaker projection 40 extending between the corner cutting edge 22a or a side cutting edge 22b and the first breaker projection 30; and the second breaker projection 40 is upward formed into a crest shape across the whole length of the extending direction on a cross section orthogonal to its extending direction and gradually rising to the rake face 21 on the cross section along the extending direction, is formed into the crest shape toward the corner cutting edge 22a or the side cutting edge 22b in the plan view, and makes the pointed part 41 of the crest shape approach to the corner cutting edge 22a or the side cutting edge 22b.

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