I’m throwing this in the 21700 Review section, but it’s sort of more info (that’s missing off Kaidomain’s site) than a tech review. The sort of info someone looking at using this host to build a project requires.
There are some pics, but nothing showing where the USB C charging port is, nor anything showing the entire host broken down. The good news is the USB C charging port is internal to the body and the midsection needs to be unscrewed to access it. So it’s (in theory) water tight as it’s protected by an O ring seal. You unscrew the mid section completely and can plug the USB C cable into the hidden plug on the thread. On top of the mid section there are also two LEDs that illuminate to indicate charging is occurring. One stays illuminated while plugged in charging and the other flashes - faster the flatter the battery is and it slows down as the battery charges. I haven’t yet waited long enough to see if the flashing LED totally extinguishes or just slows right down.
The head of the flashlight has a built in shelf for the LED 20mm board and the driver required is 22mm. Something important to note is the LED driver must have a positive spring - not a brass post. The reason being the driver screws onto the charging circuit board in the mid section. So don’t buy a Convoy driver with a brass post like I did. :person_facepalming: You might get it to work by tightly screwing the body up but the driver will sooner or later fail from the pressure exerted on the brass post. :cry:
Overall the host seems well made and of decent quality. There are O- rings seals everywhere so it should be water tight. I went for the silver with smooth reflector, fitted a neutral XHP70 6V with a Kaidomain B70 boost driver. Performance wise it’s very close to my Klarus G20L for spread and distance. The K1C actually has more even spread than the Klarus and will sustain the highest setting far longer. The Klarus dies pretty quickly and defaults to a lower output even though it isn’t even warm. The K1C does get warm, the driver is supposed to have temperature control so it should self regulate.
I have got XHP70.3 HI LED’s for both flashlights, but I might end up only fitting one in the K1C due to the Klarus too quickly reducing power.
This appears to be identical to the DongDongHai DDH-M1C, so I assume DDH is the OEM. DDH lists the charging at 1A - has that been your experience? I wish it were higher, but I do find the internal charging port quite attractive.
I have their D2G host, which is similar to a Convoy M21A but has much beefier cooling fins. Fit and finish is really great for the price, I rate it higher build quality than Convoy but the price is actually cheaper (approx $12 for the DongDongHai vs $16 for the M21A - host only)
I’ve seen the DDH version for $15 on shopee, and it’s probably even cheaper off Taobao.
Quality wise the finish on mine has a blemish, but it appears well made. The advert doesn’t mention if it’s anodised, mine almost has the appearance of paint?
I forgot to check the charge current, but bizarrely the red LED appears to continue flashing even after the battery is full (I plugged the USB power device in too late and no current was being drawn.) The blue LED is permanently on while charging too. I’ll see if I can find any info on the DDH-M1C.
Okay, charge current is only 1 Amp and a USB A to C cable must be used (like many other flash lights…)
With the tail cap turned on to charge the red LED is permanently lit when charging and the blue off. I assume the blue LED will light when fully charged.
I swapped the LED over to a 5000K XHP70.3 HI yesterday and it works quite well with that installed. There’s still some spill, but now there’s a definite hot spot. I’ll have to compare it again to the Klarus G20L for throw - seeing as I don’t have any technical type equipment to measure any changes!
Apologies for necrocomment, just ran across K1C on KD and searched and found your review.
Any chance you still have the host and can take height / diameter measurements of the reflector? Trying to see how it compares to Convoy M21B / S16 or Noctigon KR1 reflectors.
LEDiL Olga optics are kinda drop-in for M21B (30.5mm diam / 22.8mm tall) or KR1 ( 30.5mm diam / 20.3mm tall) reflectors, so MIGHT fit K1C. But Olga optics are only 18mn tall, so as long as the diameter fits, would need to add a spacer under the MCPCB or between the optic and lens.
In yours with the XHP70, only Olga-M or wider has a wide enough aperture. If you want narrower than that, could go with LEDiL Yasmeen-30-RS, or narrower still, there’s a 29mm 3° in the Jarmay store on AliExpress that might also work.
Dimensions listed for the Olga or Yasmeen-30 on LEDiL’s datasheet include the holder, so gotta take a couple mm off on each dimension to get a more accurate measurement.
One other Q: ant chance you have any of the S-series Convoy lights (S21B, S12, S16) or any of the multitude of Wurkkos or Sofirn 21700 lights that are compatible with the Wurkkos 20350 tube? Trying to figure out if the head / tail of the K1C might be compatible with the 20350 tube as well.
I was thinking you’d need the holder to use that design optic? Or isn’t it required?
I’ve only got a couple of Convoy S2+ and a Z1 (which is 21700, but probably a different thread?) The Wurkkos and Sofirn flashlights I’ve got are all 14500.
The K1C has a different (larger) body diameter/ thread diameter to the host Kaidomain sell as an “S3”. It’s 21700 and likely very similar to a Convoy 21700 S model. The S3 body threaded end easily slips inside the K1C head, no screwing required!
