Charging Time: 2H, RPM: up to 36000, Input Voltage (V): 5V, Working Current: Standard file 400 ± 10mA; strong file 500 ± 10mA, Battery Information: 800mAh, Input Current: 1A, Materials: ABS, IP rating: IPX7.
Basically copy coupon, view price history or create e-mail price alert. Let’s see what best price is ATM.
Aliexpress
There’re some similar (or not) items on Aliexpress
You can use link bot to get even lower price:
Click here to search by yourself. Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in Hong Kong.
Link: Banggood product page
1. ($29.99): BG2f1afa
2. ($30.59): BG4ee866
3. ($30.99): BGc97422
4. ($33.83): BG00c906
put item in your cart and apply coupon code there after clicking “Proceed to checkout”. Click to copy code and open shop.
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): BG4937, BGHU980, BGF1937, BGF1493, BGAFF10OFF, BGF2299, BgcLuBofErtA10, BGCF1499, BGOCLEAN2, BGOCF1, BGF14937, BG19561, BG22371, BGWT1499, BG10OFFAFF, BGMAY048, BGwhielabel, BGjune10, BGjune21, BGjune28, BGjune50, BGjuly63, 13f142, BGjuly0770, BG10OFFAFF1, BG73202c, BGa20c4f, BGcd5bb8, BG8b78ee, BGHealth06, 00c906, BGHealth10D, 2022ACTIESNL, BGHB218, BGXPAP263, tRaDetRaCKeR, BGHECARE1, BG39a0fe, BGab19c1
(these coupons are old, so probably won’t work)
Price history and price alert
Do you need price history chart (for all/most countries) for Xiaomi Oclean F1 Sonic Toothbrush? There we go. The lowest price was: $9.99.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).