Battery Type: Built-in 1800mah rechargeable lithium polymer battery, Working Time: 13h, Battery Capacity (mAh): 1800mah, Charging Time: 3h, Battery Volatge: 5V.
Price history, coupons and price alert are available on this page. You probably want to know what is the best price?
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 price update (UTC time):
Banggood
Banggood warehouse is located in China. I can’t find any active coupons for this product in Banggood.
Link: Banggood product page
Price: $-3
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): e2bcea, elec, BGCITYADS2019, 7bcdf9, BMPlayers, BGVDay10%off, BGAFF10OFF, BGTT10, bGhOnEy10, Email5, BGXDUOOX32, BGSS10%SW, 7d18f7, bgshOOp10, BGELIG0920, BG11SHOP, BG11PP12, BG11PP7, BGXDX3II12, 13f142, BGCuponation10, 6GSGIT, BGBRPL2, BGHOTSHOP15, BG53e9c8
(system checks these coupons on every price check (like once per 24 hours), but you can check them out anyway)
Other warehouses/versions
This item is available in 1 another warehouse/version!
1. Europe – XDuoo X3II Music Player [EU] ($-3)
Price history and price alert
Price history (for all/most countries) for XDuoo X3II Music Player is here. The lowest price was: $89.99.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).
Unfortunately, its price was increased to 127.9$. hopefully, there will be any coupon or deal on it soon, as I want to buy it soon