Abstract: Envelopes of different dimensions opened on three edges, namely one short edge and two long edges, are fed standing on one of the opened long edges to a removal device, in which both envelope sides (U and V) are deflected to the left and right by approximately 90.degree.. The envelope contents (Z) is conveyed linearly out of the removal device. The removal device is formed by two vertical suction cylinders (25, 26) positioned to the left and right alongside the envelope and which, under sensor control, engage the envelope sides, deflect them by approximately 90.degree. and consequently separate the sides from the envelope contents. The envelope is then ejected at one side, and the unopened short edge at the rear of the envelope assists the linear movement of the contents out of the apparatus. A third cutting or opening mechanism (23) for the lower long edge forms, together with the suction cylinders (25, 26) and the other rotated parts of the removal device, a compact constructional unit.