You can get 4Pcs USB Rechargeable Fridge Deodorizer for $18.99 with coupon (from Banggood). Basically copy coupon, view price history or create e-mail price alert. Do you want to know what the best price is?
2PCS / 4PCS USB Rechargeable Fridge Deodorizer Multifunctional Ozone Machine Compact Air Purifier with Two Modes for Effective Odor Elimination Extend Food Freshness Lightweight Portable for Home Travel – 4Pcs
Latest coupon and price update (UTC):
Banggood ($18.99)
Banggood warehouse is located in China. Is it cheap? Hmmm, price is higher than average (which is $17.99 right now), so better set price alert down below… I found coupon for you. Check this out.
Link: Banggood product page
Price without coupon: $33.99
1. ($18.99): BGAnnivHG04
coupon code has to be applied in shop’s cart after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BGbf612c, BGHOBBY142, BG3e3606
(these codes were not working in latest coupon update, but you can check them out anyway)
Aliexpress
There’re some similar (or not) items 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 4Pcs USB Rechargeable Fridge Deodorizer.
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)).