Aliexpress
Click here… to search for Digoo DG-MR10 Ultrasonic Mosquito Killer on Aliexpress
Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China. There is one coupon available! Pretty cool, huh?
Link: Banggood product page
Coupon (7.55 USD): BGAFF10OFF
(CouponsFromChina.com tip: just apply this code 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): PICODICOM, 0404digoo, BGDGMR10, BGDigoo15%, BG50MR10, BGALHUBF, BGAPPLIANCE, BGAPPLIANCE1, BGFTDY, BGDMR10, BGDG110, BGTT10, 20%DG422, bGhOnEy10, BGDGMK, BGSS10%SW, BGHome15%, BGHOMEAPP13, BGHOMEA13, BG11SHOP
(probably won’t work, but you can try them out)
Price history and price alert
Here is price history (for all/most countries) for Digoo DG-MR10 Ultrasonic Mosquito Killer.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).