You can get MH-665 Non-Contact Air Blowing Alcohol Tester for 14.39 USD with coupon (from Banggood). Price history, coupons and price alert are available on this page. Let’s see what best price is ATM.
Latest coupon and price update (UTC):
Banggood (14.39 USD)
Banggood warehouse is located in China. Is it a low price? Maybe there’re no more promotions for this item, because current price is higher than average (which is equal 11.94 USD) There is one coupon available! Pretty cool, huh?
Link: Banggood product page
Price without coupon: 15.99 USD
Coupon (14.39 USD): BGAMMT03
(CouponsFromChina.com tip: apply it in your cart after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BGSCM11, BGc61b96, BGCRT313
(I don’t think these’re gonna work, but you can try ’em out anyway)
Aliexpress
Here are coupons that you can use.
Price history and price alert
Check out price history chart (for all/most countries) for MH-665 Non-Contact Air Blowing Alcohol Tester.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).