Output: 5V=3A*2, 9V=2A*2, Unique Tech: QC3.0, 12V=1.5A*2 MAX 36W, Input: 12-24V/2.4A.
Go down and check coupons out. Remember to check price history if it is available. Do you want to know what the best price is?
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 code price check (UTC time):
Banggood
Banggood warehouse is located in China. You can get coupon down below.
Link: Banggood product page
1. ($14.39): BGAFF10OFF
just apply this code 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): TTxBG10, BG3CSUM, AFfbG10, bGpAnDacHeCk, BGVDay10%off, bGhOnEy10, BGXMI15, BGdragonBoat, BGXiaomidual, BGXiaomi88999, bgshOOp10, BgoFErTaSchInA10, BGHALLOWEEN, BgcLuBofErtA10, BG20CHARGER, BGMBCBLE
(you can check these old coupons out, but these probably won’t work)
Price history and price alert
Check out price history chart (for all/most countries) for Xiaomi QC3.0 X2 Metal Dual Car Charger. The lowest price was: $8.99.
Price records source(s): 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)).