Weight 400g (net weight), LED life 100.000 hours, Waterproof 0-100m underwater, Lumens 1000 lumens, Neutral White 4000K, Size (mm) About 180x56x32mm, Model SD09, (length * head diameter * tail diameter), Color Temperature Cool White 6000K, Mode Strong light/dark light, Illuminable use 3 hours in strong light/6 hours in dark light, Battery configuration Built-in one 26650 battery, LED model XM-L2.
Basically copy coupon, view price history or create e-mail price alert. Let’s see what best price is ATM.
Aliexpress
There’re some similar (or not) items on Aliexpress
You can use link bot to get even lower price:
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. You can get coupon down below.
Link: Banggood product page
1. ($35.19): BGTorch4
put item in your cart and apply coupon code there after clicking “Proceed to checkout”. Click to copy code and open shop.
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): BGSD09, BgoFErTaSchInA10, FIN6876, bGhOnEy10, BgcLuBofErtA10, BGFLS15, BGAFF10OFF, BGCuponation10, 4BLF, BG10OFFAFF, BGwhielabel, BG10OFFAFF1, BANGGOODSD
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Here is price history (for all/most countries) for SEEKNITE SD09 XM L2 Diving Flashlight. The lowest price was: $35.19.
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)).