Abstract: This mechanism includes a housing having three, equi-angular spaced, radially projecting arms which carry pivotal hook members that are releasably engagable with the rim of a wheel to secure the housing on the wheel for rotation therewith. Each hook member is adjustable longitudinally of its associated arm so that the mechanism can be mounted on wheels of various diameters. A circular casing, which is mounted on the housing normally to rotate therewith, carries an adjustable mirror having on its rear face a triangular plate held resiliently against a plane surface on said casing. A plurality of adjusting screws on the casing are engagable with the mirror to tilt it selectively about any one of the three edges of the triangular plate to position the mirror's reflecting surface in a plane normal to the axis of the rotation of the wheel. The casing can be rotated manually relative to the housing to adjust the tilting edges of the plate.

Abstract: A mirror is mounted in the open end of a circular housing by means of a universal joint formed by a stud which projects from the rear of the mirror into a spherically-shaped knuckle joint that is seated at diametrally opposite sides in a pair of "Teflon" ring bearings carried by two plates that are held over opposite sides of the knuckle by a pair of adjusting screws which can be selectively tightened or loosened to control the resistance to movement of the mirror universally about the center of the joint. The housing is releasably attachable to the hub cap of a front wheel by a plurality of clamps adjustably mounted on arms which project radially from the housing.