I noticed that this thread is a bit old, but some questions are still unanswered, so I will try to shred some light around "these" flashlights.
First of all, this flashlight seems to sell under different model names i.e. DH30, WH33, WH36 etc. (They have made design changes to the flashlight, but it seems to be sold under the same model names regardless of the changes made).
I purchased 2 units through Alibaba, It took approx. 2 weeks for the units to arrive.
Service and handling was very professional (and the price was superb) J!
For each flashlight I ordered, I received:
- Two spare O-rings, to seal the canister
- Nice metal box to carry charger, batteries, and flashlight
- The flashlights (with cord and canister, all mounted together)
- A brief manual
Looking and comparing the shipped (2) flashlights with the product pictures from Alibaba, I noticed that the shipped flashlight where different in their design.
The front plate (lens) of the flashlight housing was mounted with 4 screws, not 6 as shown on the picture. The 6 screw setup (as shown on some Alibaba pictures), will certainly seal in a better way (to avoid leakage/flooding into the flashlight housing).
In addition, the cable connection towards the housing and canister, are not always made in metal as shown on the Alibaba pictures (certainly not on the units I got). However, they look sturdy and well made even without the metal version.
As long as the flashlight operates to specification, the differences are not equal to any issues!
I had planned some dives to test the flashlights thoroughly.
Here are my test results and conclusions:
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Flashlight 1
First dive was planned for 40min with a max depth of 28m.
Everything turned out great, and my dive buddy was impressed by the light.
"So far so good", they even started talking about ordering more units (through me) J
Second dive was planned for 40min, with a max depth of 35m.
First half of dive passed by with no issues, at 35m depth, 20 min into the dive, the flashlight suddenly "blacked out". My initial thought was that the batteries were drained.
Arriving at surface I headed back home.
I recharged batteries at home, while testing the operation with a new set of charged batteries.
It seemed to operate ok, so my conclusion was that I needed an extra setup of batteries for 2 dives in a day. Couple of days later I took the flashlight out for a new test.
Now everything went bad L
Prior entering water, I tested the flashlight and it seemed ok.
2min into the first dive (at approx. 5m) the flashlight "blacked out" again!
Returning to surface and boat for inspection, I first noticed that the canister was flooded.
Drying the batteries and testing flashlight, it went on, but suddenly changed mode??
My "expertise" tells me that the electronics inside the flashlight housing had been flooded.
So I inspected the housing and…. Yes, water was inside the unit on the wrong side of the green illuminating O-ring!
Back home I disassembled the complete unit and noticed week torque on all mounting screws, and significantly lack of silicone grease. In addition 2 of the used batteries were not working anymore.
Flushing unit with sweet water, drying, lubricating with silicone grease, and mounting everything together, it now seems to work as intended. However, not yet tested in the ocean!
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Flashlight 2
Being a little curious if the issues with flashlight 1 were a fluke accident at the manufacturing, I started to inspect flashlight 2 closer (I don't want to take it out diving just to have it flooded at the first dive).
I noticed the same issue with poorly attached silicone grease at manufacturing, so I decided to take the flashlight a part, and redo the same procedure as I did on the first flashlight.
Now this was a lucky strike!
When I opened the backside of the flashlight housing, I first discovered that one of the four screws assembled at the back of the flashlight unit, was slightly damaged (causing issues to have it removed).
In addition one of three O-rings in the flashlight main unit was damaged!
The damaged O-ring was clearly caused during assembly at the manufacturing, due to poorly usage of silicone grease.
So now I had a brand new flashlight that I needed to disassemble, lubricate with silicone grease, and change of an O-ring prior its first usage!
Main issue at this moment was the damaged O-ring (since it wasn't provided as spare. only the ones used in the canister were provided).
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On the positive side:
I have to give good credit for the good service during purchase and for sturdy well-made units.
The issue seems to be the assembly part of the manufacturing process.
Working with manufacturing myself (not within the diving industry), I have a good insight regarding importance of the complete manufacturing process.
The issues have not been solved yet, but I still believe that these lights will operate well after some "minor" adjustments (reassembly made by me). Future dives will tell!
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