Basically copy coupon, view price history or create e-mail price alert. What is best price?
Battery type 18350 Li-ion battery, Weight 100g ± 0.5g (excluding battery), Dimensions (head diameter) 31.5mm / (length) 117mm±0.5mm, Switch Tail push button switch, Anti-drop height 1M, Waterproof IP67, Material Aluminum alloy, Light source High power white light X-LED
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):
Banggood
Banggood warehouse is located in China. We have found one coupon for this product!
Link: Banggood product page
1. ($205.04): BGOutlight10
apply code in your basket (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): BGAlerabatI, BGtorch9
(you can check these old coupons out, but these probably won’t work)
Price history and price alert
Here is price history (for all/most countries) for Weltool W35B/W35C Rail Tactical Flashlight.
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)).