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. :FACEPALM: 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. :((
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.
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!