Review title is No Li-ion battery and not waterproof! [SEP] Wow. It's 2018 and this thing comes with NiMH batteries instead of Li-ion?? How did I miss that-? It's my bad of course. Claims 10 days of charge. It is also not very happy getting wet it seems. &quot;Do not use while bathing.&quot; That's one of my favorite things to do with my Sonicare.  I LOVE the looks of this thing and was willing to pay the price but no Li-ion and not being able to use it in the shower ... wow. And replacement heads are $20 for 2. I am so eager for someone to make a USB chargeable electric toothbrush that is well thought-out.