Just check coupons out (with price alert and history). What is the best price?
Voltage: DC 12V / 24V AC 100 – 240V 50 – 60Hz, Cooling range: 20 to – 20 Deg.C, Capacity: 40L, Power: 45W, Refrigerant: R134a, APP: Smart car fridge, Material: Poly bag + poly foam + ABS, Noise: <45dB
Aliexpress
I could not find it on Aliexpress. Click here to search by yourself.
Here are coupons that you can use.
Latest coupon and price update (UTC):
Price history and price alert
Check out price history chart (for all/most countries) for Tecney CX40 40L Car Freezer.
Price records source(s): Gearbest
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)).