① Is the voltage is fixed or variable?

HF-8Whisper,HF-7Premium and HF-7Classic are counter-top oral irrigator and their’s voltage are fixed.We could make any voltage that fit certain countries.And HF-3Premium is for traveling and the voltage is variable between 100-250V.

② What is warranty of the products?

One month for replacement and 2-year for repairing.

③ One product is for one person or could for other families？

As long as each one has there own color tip,it could be for other families.

④ Can use mouthwash instead of water?

Yes,it can.Mouthwash and salt water are both ok.

⑤ what kind of battery does rechargeable type use?

It’s Ni-MH battery.

⑥ Does it replace floss or toothbrush totally?

It just replace floss and not toothbrush.

⑦ Is it loud when using?

The noise of HF-8Whisper is much lower than many other oral irrigators.

⑧ Is it waterproof?

HF-8Whisper,HF-7Premium and HF-7Classic is IPX-7 waterproof.HF-3Premium is not waterproof for it is in low-voltage.

⑨ Do I need a transformer when using in another country?

It depends on the voltage of the country,it needs a transformer if in different voltages.

⑩ How long will be the battery last when fully charged of HF-3Premium?

About 15 times of refilled water.It depends on the interval time of using.