The is particularly important when you are parked on the side of the road that means you will be getting out of the car straight onto the road.
Using the opposite arm will force your body to turn to that side and means you will be able to spot whether there is a cyclist coming your way.
This method keeps cyclists safer and, for that reason, there have been calls in the past to make this method part of the requirements to get a driving licence in New Zealand.
While it is not a requirement in New Zealand, it is a useful technique that drivers can use to keep people around them safe and prevent dooring cyclists.
Data from the Accident Compensation Corporation (ACC) shows it received nearly a claim a week from cyclists hit by car doors in 2017, and paid out more than $58,000 in compensation for those accidents that year.