The product serial number is on the back of the product or the sticker label on the product packaging's exterior sleeve. 

Wipe the AC01 clean with a slightly damp or antistatic cloth. Never use aggressive detergents, solvents or products containing abrasives.  
If liquids get inside the product:
Remove the back cover immediately.
Open the three battery compartments and remove the batteries.
Remove any excess liquid with a cloth.
Leave the AC01 face up in a warm and dry place for at least 72 hours (do not put it in a microwave, an oven, or any other electrical appliance).
Do not reinsert batteries until the clock is completely dry.
Products may be damaged if internal components are exposed to liquids. The warranty does not cover liquid damage.

The AC01 has three batteries: one for the clock and alarm and two for the light. The batteries work for separate functions, so they won't necessarily all need replacing at the same time. Battery compartments are illustrated with icons that indicate their function. 

Type: IEC LR44
Ensure that the battery plus sign is facing upwards.

Press the button on the rear of the clock beneath the down arrow to open and remove the back cover.
Open the battery compartments using a coin to turn the cap, lift out the old battery/batteries and remove.
Replace with new IEC LR44 batteries and close.
Check battery pull tabs have been removed.
Ensure that the battery plus sign is facing upwards.
Ensure battery compartment covers are closed properly.
Check the AC01 is ticking.
Replace clock batteries (battery compartment showing the clock icon).
Use battery type: IEC LR44. 
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