Abstract: A metal-cutting insert for performing cut-off and grooving operations and of the so-called self-gripping type. The insert comprises a front end with a cutting edge, first and second elongated straight grippable surfaces extending in converging relationship rearwardly from the front end and a rear end defined by first and second straight surfaces of approximately equal length that intersect each other in an included obtuse angle. The grippable surfaces each have a concave transverse contour. The first and second end surfaces extend respectively from the first and second grippable surfaces and intersect at a location to coincide with the intersection of a rear locating surface and a key-receiving aperture of a support blade when the insert is fully received within the support blade recess.