Just check coupons out (with price alert and history). You probably want to know what is the best price?
Wide angle: 70°, Battery type: 4 Cells AA Batteries (Not included), Display screen: 2.4 inches, Camera OD: 5.5mm, Camera pixel: 1.0MP, Effective focal length: 3~10cm, Cable Lenght: 1M /3M (Optional)
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. There are no active coupons for this product, but the price is pretty low isn’t it?
Link: Banggood product page
Price: $-3
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BGTDL01, BG93dc4d, BGe52d22, BGTools8, BGCL88, BGGines
(these coupons are old, so probably won’t work)
Other warehouses/versions
This item is available in 1 another warehouse/version!
1. Europe – Professional Industrial HD Borescope with 2.4 Inch LCD 5.5mm 3m [EU] ($-3)
Price history and price alert
Price history (for all/most countries) for Professional Industrial HD Borescope with 2.4 Inch LCD 5.5mm 3m is here.
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)).