Aliexpress
Click here… to search for SEEKNITE S3 SST40 Flashlight on Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. Only one coupon available!
Link: Banggood product page
Coupon (28.33 USD): BGTorch4
(CouponsFromChina.com tip: 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
Old coupons (from the oldest to the newest): BG10OFFAFF1, BANGGOODSD
(these coupons are old, so probably won’t work)
Price history and price alert
Price history (for all/most countries) for SEEKNITE S3 SST40 Flashlight is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).