Direct power supply measurement range: DC 8-100V, Individual power supply range: DC 5-12V, Measurement range: DC 0-100V, Display format<10V, Acurancy: ±1%. Go down and check coupons out. Remember to check price history if it is available. 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 code price check (UTC time):
Banggood
Banggood warehouse is located in Hong Kong. There is one coupon right now! Check this out.
Link: Banggood product page
1. ($13.15): BG00c906
coupon code has to be applied in shop’s 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): BGRCParts8, BGJUNEGSG9, Cuponation9, 9OFFSUMMER
(you can check these old coupons out, but these probably won’t work)
Price history and price alert
Do you need price history chart (for all/most countries) for Peacefair PZEM-023 0-100V Voltage Tester? There we go. The lowest price was: $10.91.
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)).