Warning triangle for motor vehicles

The triangle has an inverted-T shaped, horizontally positioned base rail (2) comprising sockets (22) at two end parts for rotatably receiving rotatable ball-and-socket joints (71) of wire stands (7), if horizontal longitudinal axis of the stands is parallel to horizontal longitudinal axis of the base rail. The sockets are formed as horizontal U-profiles, where a lower arm of the U-profile is formed under a horizontally surface of the base rail in the form of inverted T, such that the lower arm is inwardly opened in one direction.