To anyone who wants to ride more safely I cannot recommend enough this simple $20 mirror which I find so valuable that I buy extra and hand them out to friends and strangers to help keep them safer. A mirror mounted on your glasses or a similar mirror affixed to your helmet (close to your eyes and mounted on your head) allows for a large field of view that you can easily steer to see behind you.

I ride on the streets of Oakland every single day and situational awareness is critical. The single biggest thing you can do for safety is watch each car as it approaches behind you for its speed and trajectory. Anyone approaching too close or too fast is a bad sign and with a mirror you can more easily avoid them.

These are also available on Amazon and I am not in any way affiliated I just think they’re good life saving technology:

https://takealookactive.com/