This particular switch is pretty clever. There are no springs and the only part for potential corrosion is the magnet in that little slider. A couple other “dive lights” with Hall sensors I got have springs and things on the outside. Sure, no hole through the light for a switch, BUT the mechanism is cheap carbon steel and rusts out fast in saltwater immersion use. This is the first light I’ve gotten that does not do that. Seems reasonably solid.
FWIW, the seal on the back of a twisty is just as vulnerable when static as dynamic as long as the O-rings are in good shape, well lubed, and not contaminated with cat hair or other debris. Most floods of a properly designed light are user errors. MANY floods on Chinese lights are due to shoddy materials and poor workmanship. I don’t trust ANY of them until checked out thoroughly and defects corrected……if possible.
It’s one thing to have a light fail on a dark walk. It’s entirely another if you are depending on it during a dive. That’s why we carry 2 (or more) lights.
Took the UKing (pretty close to the DV) on a dive yesterday. Used it for 1 hour with a Lii-26650. Worked fine, nice spot. Came back with half capacity.
Salt. This wasn’t a deep one, 60 feet/68 minutes. What I like about this light is the apparent lack of external springs that rust out in many of the other models of cheap dive lights not ACTUALLY designed for serious diving. This one might work out. Oh, and NO modes…just the slider from dimmer > full on. Gotta like that.
I just received a DV-S9 from FT - under $18 with BLF code, and i’m impressed.
Very nice 26650 light with magnetic switch for the price. Although it’s not a top performer it seems, i especially like the slider smooth operation…. I lubed the tail cap and o-rings while loading a 26650.
Not sure when/if i will have a chance to use it underwater. I got it as a backup to a (still unused) Solarstorm DX4. :person_facepalming:
PS: thanks to the above comments about the red ring preventing the switch to fall off. Mine was loose and i wasn’t sure what this ring was about nor did i noticed it would actually screw in. I would probably have lost the slider at some point. :+1:
I don’t know how to test this but I believe the flashlight has a rather high parasitic drain. I left a battery in there unused for several weeks (< 1 month), and the battery was drained to below 2V when I tried to use the flashlight. As this isn’t a flashlight I would use once every week, I don’t leave battery in there anymore till I want to use it.
Even when “off”, the Hall-effect circuit for the slider draws something like 10mA. I mentioned it somewhere in this thread, so I think that’s how much it was. Not at all unusual or unreasonable. But yeah, I always gave the beastie a quarter-turn lockout when not in use.
Diving lights can also be used to pick up divers from the surface if they get caught in a current and drift away from their dive site. Sounds like a good idea to me.
Did a 31 dive vacation (Lembeh, Indonesia) beginning of the month. The DV-S9 worked without a problem going to 90+ feet a few times. The only unexpected issue was the magnet is embedded in the black slider. This was a sandy area (muck diving for weird critters) and the light would often rest on the bottom during during photos. It picked up iron grit. Didn’t affect use in any way. I didn’t even notice it until I got home and was cleaning things up thoroughly. I was able to remove it with small strips of tape and finished with high pressure air.
I did notice some minor fogging in the lens with use. There were a couple micro-drops on the lens. There was no evidence at all of flooding from the front or back. I think it was condensation, probably during assembly. Removed the front lens. The red rig holding the lens in has a silicone O-ring and there is a main O-ring under the lens. It’s been fine on extended dunk tests but has not gotten a dive test since the disassembly.
