How to use a UK electric toothbrush in the USA?

kutekitty

Hope this is the right forum!

My elderly relatives are traveling to the USA, and need to use their braun electric Oral-B toothbrush in the USA (They can't use a manual toothbrush as they have some tooth condition).

On the charger it says: 220-240V ac, 50-60HZ/1,2W
Type 3757

If I purchased any of the following, would it allow the charger to work?:
I am not sure if a UK toothbrush charger would fit into the holes in the plugs and if the voltage would convert.

Item 1) 110V to 220V STEP UP VOLTAGE CONVERTER 50W TRANSFORMER US CHARGER PLUG ADAPTER ! 39612100075 | eBay


Item 2) UP CONVERTER VOLTAGE ADAPTER 50 Watt StepUp 110v to 220v For forengn device  | eBay

Also, would a 220v-to-110V work or does it have to be 110v-to-220v

Thanks!

LV426

May I suggest, as an alternative, them getting a toothbrush that runs on regular batteries, like:
https://www.amazon.co.uk/Oral-B-Advance-Power-Battery-Toothbrush-x/dp/B0036TH5VO/
for use when travelling.  It depends on how they work it, but arguably they'd only need one base unit, and this will be cheaper than a transformer.  No bells & whistles like bluetooth or timing stutters etc., but it will do the job, and power is (obviously) no problem - just buy more batteries locally.  This is exactly what I do when travelling outside Europe (etc).  

But to answer your question you need a 110 TO 220 transformer.  110 input; 220 output.  I imagine either of those you suggest would work