Your bargain sensors should be tingling – it’s just $29.99 (Banggood). DUKA Portable Alcohol Tester Non-contact Breath Analyzer LCD Digital Display Rechargeable High-precision Alcohol Tester Tool – #01.
Updated:
Banggood
Warehouse in China.
Link: DUKA Portable Alcohol Tester Non-contact
Price: $29.99
Additional Banggood coupons:
1. First page
2. Second page
Aliexpress
I could not find it on Aliexpress. 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 DUKA Portable Alcohol Tester Non-contact. The lowest price was: $23.69.
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)).