Abstract: The rotary switch consists of a plurality of switch decks and is designed to be mounted on a support (2) by a mounting plate (3). At one of its ends it is operated by a control shaft (4) which actuates contacts by cams (5) located in switch modules (9,10). The moving members of a plurality of electrical contacts are also located in the modules stacked about the control shaft. The switch body is provided with two through holes (13, 14) aligned with the axis of the control shaft (4). One of the holes goes through the mounting plate (3) and the other through an end plate (12), at the opposite end of the switch from the mounting plate. Each through hole allows the shaft to rotate therein as required. The mounting plate (3) and end plate (12) includes a ring recess (15 or 16) for ring (17) serving to limit the angle of shaft rotation. One of the through holes includes a lock (19) for locking against axial movement the assembly formed by the shaft and the cams it controls.