Rear view mirror for cyclist is attached by ball joint to end of arm whose other end is attached by second ball joint to support fitting on to cycling helmet or spectacles

摘要

The rear view mirror (1) for a cyclist is attached by a ball joint (3) to the end of an arm (2). The other end of this is attached by a second ball joint (4) to a support (5, 6) which fits on to a cycling helmet. Alternatively the support may be in the form of a three-pronged fork which fits over the front or arm of a pair of spectacles.