Insert and clamping holder having four-point contacts

Cutting insert for grooving or cutting off, comprising an upper side and a lower side, which are configured to engage, in each case, with opposing sides of a recess, between which the cutting insert is clamped,

• wherein one of the sides has first and second spaced-apart contact points and the other of the two sides has a third contact point and a stop, which is spaced apart therefrom, limits an insertion depth of the cutting insert into the recess and simultaneously also acts as a further, fourth lateral contact point,
• wherein sides of the cutting insert are concave and convex analogously to sides of the recess, the side having two contact points being concave and the side with one contact point being convex,
• wherein the stop comprises a stop surface at an end of the cutting insert remote from a cutting edge, and
• wherein the stop surface is angled with respect to a curved course of the respective side by an amount of 15 to 50°, such that the stop simultaneously acts as a further, fourth sideward contact point, the cutting insert thus comprising four contact points.