$7.99 – KWS-DC28 Current Voltage Tester 4-30V 12A (Banggood, Aliexpress: KWS-DC28 Current Voltage Tester 4-30V 12A Digital Ammeter 0.96-inch TFT Display High Precision Compatible with DC Devices – Black (the best price with coupon)).
I have just checked coupons. The lowest price I could get is $7.99 for KWS-DC28 Current Voltage Tester 4-30V 12A (in Banggood). Basically copy coupon, view price history or create e-mail price alert. Do you want to know what the best price is?
Latest coupon and price update (UTC):
Banggood ($7.99)
Banggood warehouse is located in China. Good or bad price? Actually this is the best price in history according to CouponsFromChina database! Only one coupon available!
Link: Banggood product page
Price without coupon: $8.99
1. ($7.99): BGf8e1ff
paste coupon code in your cart and click Apply after clicking “Proceed to checkout”. Click to copy code and open shop.
This is the best price ever noted in my database!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/feV
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.
Price history and price alert
Do you need price history chart (for all/most countries) for KWS-DC28 Current Voltage Tester 4-30V 12A? There we go. The lowest price was: $7.99.
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)).