The invention relates to a combined mechanical and key comprising a key housing for electronic components and an L-shape flat key (30). Said flat key consists of a bearing limb (31) which enables the key to pivot into a storage position and a shank (32) which mechanically operates the lock. The shank (32) of the flat key (30) can be displaced between an inoperative position, retracted into the key housing and an operative position, in which it projects out of the hosing. A push-button preferably also acts as the pivoting axis for the flat key (30). The push-button and the housing have profiled sections and the bearing limb has co-operating profiled sections (37, 38, 39), to subject the flat key (30) to a force in the operative position and to lock the key in one of its positions. The invention aims to produce a simple, cost-effective key. To this end, the flat key is configured as a planar plate (34) with an L-shaped outline, the shank (32) sharing the same plane as the bearing limb. The bearing limb (31) has an opening (35) in the plate for receiving, in a rotationally fixed manner, an insert (36) that has the co-operating profiled section (37 to 39).