An arm (3) for a pair of glasses made of two sections (6, 7) is described, which are connected to one another via a coiled spring (10), which forms an arm joint (8) and is enveloped using an elastomeric plastic envelope (9). In order to achieve an advantageous bending behavior for the arm joint (8), it is proposed that the plastic envelope (9) have a differing wall thickness around the circumference, which determines the bending resistance of the arm joint (8) with respect to at least one predefined bending axis.