Door mirrors are also acceptable Howard!
From memory the legal requirement is one on driver's side and a second either on the left or a central (windscreen mounted) mirror.
Trouble is, car driving test / instruction still relies on use of central mirror, with scant attention paid to either side.
Even driving a car the "lifesaver" glance over the right shoulder (when driving on the left) is still very much in use by me
35 years on two wheels makes one maintain good all round observation.
