Switchable support element for a valve train of an internal combustion engine

A switchable support element for a valve train of an internal combustion engine, said support element comprising a housing that can be arranged through an outer peripheral wall in a reception of the internal combustion engine and in whose bore an axially movable inner element extends, a head of the inner element protruding beyond an edge of the housing, coupling elements being associated to the inner element for a selective coupling of the inner element in an axially extended position of the inner element to the housing, and said inner element being biased by at least one lost motion spring in a direction leading out of the housing, wherein the coupling elements are at least one slide which, in case of uncoupling, is positioned in a guide of the housing extending in radial or secant direction and which comprises a flattened upper side starting from a radially inner front end of the slide, and this flattened upper side can be brought into engagement with a flattened lower side of a recess in the outer peripheral wall of the inner element for effecting coupling, the recess of the inner element is configured as one of a transverse slit comprising a straight slit base, an annular segment or a sickle-shaved portion in the outer peripheral wall of the inner element and is arranged opposite the respective slide as coupling element.