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: Liftgate disassembly/assembly
1. Disconnect the negative battery cable.
2. Remove the liftgate lower trim.
3. To remove the liftgate outer handle and liftgate key cylinder, remove the
rear finisher.
4. To remove the stud ball, separate the stud ball and the stay damper.
5. Disassemble in the order indicated in the table.
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Mazda 6 Owners Manual: Saving Fuel and Protection of the Environment
How you operate your Mazda determines how far it will travel on a tank of fuel.
Use these suggestions to help save fuel and reduce CO2.
Avoid long warm-ups. Once the engine runs smoothly, begin driving.
Avoid fast starts.
Drive at lower speeds.
Anticipate when to apply the brakes (avoid ...