Cup material: reflective aluminum mirror cup., Switch: enjoy the lantern in deep water with magnetic control switch, Lighting distance: 100m, maximum current 3A, Body color: black, Operating voltage: 2.8-4.3 V, LED Color temperature: 5350 K-5700 K, Water resistant: IPX8, Premium type Ⅲ Hard anodized anti-abrasive finish and better heat dissipation, Casing material: 6061 aeronautical grade aluminum, LED type: LED XPL with a lifetime of 100000 hours., Model name: SD02, Battery: powered by 1 3.7V 18650 battery pack, Lumens: 1050LM max., Net weight: 180g (does not include battery).
Go down and check coupons out. Remember to check price history if it is available. Let’s see what best price is ATM.
Aliexpress
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Click here to search by yourself. Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
1. ($20.73): BGSF
2. ($21.95): BGTORCH
you should apply the coupon in your cart 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): 502C6B, e2bcea, linepayflt, EYBG, BGBSPX, BGBFCR41, fInbG2020, BGff2020
(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 Sofirn SD02 Diving Flashlight. The lowest price was: $16.09.
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)).