Floor mats
WARNING
Make sure the floor mats are securely hooked onto the retaining pins to prevent them from bunching up under the pedals:
It is dangerous to use a floor mat that is not secured, as it may interfere with the use of the accelerator and brake pedals, and an accident may result.
Do not stack two floor mats on top of each other on the driver's side:
It is dangerous to stack two floor mats on top of each other on the driver's side, because the retaining pins cannot prevent only one floor mat from sliding forward.
If using a high-resistance winter floor mat, always remove the original floor mat.
If the floor mat(s) is (are) not secured properly, it will interfere with pedal operation and an accident could result.

When installing a floor mat, position the floor mat so that its eyelets are fully placed over the pointed ends of the retaining pins.
Test yourself
A quick Mazda 6 quiz: every answer comes with an explanation and a link to the manual page.