Compatible: 10440, 14500, 14650, 16340, 17335, 17500, 17670, 18350, 18490, 18500, 18650, 18700, 20700, 21700, 22650, 25500, 26650, A, AA, AAA, AAAA, C, SC, Input Voltage: DC 5V, Output Voltage: the voltage required by the product itself, Input Current: 2.1A, Output Current: 2A / 1A.
Check coupons or create price alert down below. 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 coupon and price update (UTC):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
1. ($16.02): BCNLXK
2. ($16.02): BGSPR
3. ($17.02): BGSM30%
you should apply the coupon in your cart 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): BGVC2S, M4BG, BF0E60
(there’s a little possibility that old coupon will work)
Price history and price alert
Price history (for all/most countries) for Xtar VC2S Battery Charger is here. The lowest price was: $12.59.
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)).