Bottle holders are on the inside of the doors.

CAUTION
Do not use the bottle holders for containers without caps. The contents may spill when the door is opened or closed.
Cup Holder
Storage CompartmentsMazda 6 Owners Manual: Front seat belt removal/installation
Warning
Handling the front seat belt (pre-tensioner seat belt) improperly
can accidentally deploy the pre-tensioner, which may seriously injure you.
Read SERVICE WARNINGS before handling the front seat belt. (See SERVICE
WARNINGS.)
Warning
The side air bag sensor is attached to t ...
Mazda 6 Owners Manual: Control system
L.H.D.
R.H.D.
...