$21.99 – 3in1 Multifunctional Electric Field Magnetic Field RF Radiation Detector Handheld Electromagnetic Radiation Tester EMF Meter Portable Radio Frequency Detect Meter – white.
When I was updating this page, then coupon price was $21.99 for 3in1 Electric Field Magnetic RF Radiation Detector (in Banggood). 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?
Latest price update (UTC time):
Banggood ($21.99)
Banggood warehouse is located in China. Hmmm… There is no active coupon in Banggood at this moment. Is it good price? According to my database, the average price is $24.59 and current price is $21.99, so it’s probably a good price!
Link: Banggood product page
Price: $21.99
Additional Banggood coupons: first page and second page
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
Check out price history chart (for all/most countries) for 3in1 Electric Field Magnetic RF Radiation Detector. The lowest price was: $19.99.
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)).