SZFEIC has kindly sent me this SZFEIC KE11 Keychain Flashlight and I want to share my opinion about this tiny flashlight.
This is my first “review” of anything, so take it lightly. English is also not my native language, so sorry for the grammar mistakes 
The flashlight was nicely packed. Inside there are:
1 x KE11 keychain flashlight
1 x keychain ring
1 x usb a to usb c cable
1 x user guide
1 x warranty card
The user guide is in english and chinese. I find it nice that they included the runtime graph in the user guide somehow as well as the illustrated operation instruction.
The KE11 body is made of aluminium and really nice processed. There are no sharp edges, everything is smooth. The top is slightly curved. The indented curve behind the switch has a subtle lined texture. Not sure what is that for but those details give the flashlight a premium feel.
I’m not sure what the button is made of, but I assume it is a plastic. However it doesnt feel cheap though. It is not slippery and if I use my nail, it feels like it has a fine texture. It doesn’t wobble.
The usb-c port cover is also good, it sits tight. The usb-c port itself has a rounded indentation and I think it will compatible to most usb-c cable head.
The KE11 has 2 LED and 1 indicator LED.
Press 1 click while OFF and it will show the battery status. It will also flash red while charging (will turn green when it is full charged).
The KE11 has a perfect size for a keychain flashlight in my opinion. It is thin (~11mm) and has short length.
Regarding the UI:
hold button : turn on/off
1 x press button (while ON): cycle through brightness level high → mid → low → moon
1 x press button (while OFF): show battery status (green 70-100%, flashing green 30-70%, red <30%)
It will memorize the last mode used when turned off.
The beam profile are fine but it could be better. It has a white bright spot in the middle surrounded by yellowish spil. I think because the TIR lens. Beam profile taken ~30cm from the wall.
Moon mode is not really a moon mode, since it is still quite bright, however this is the mode that I mostly use indoor.
Low - Mid modes are similar and can be used if you go for a walk and dont want to take a real flashlight.
The high mode with 260 lumens is bright and more than enough for a keychain flashlight. It is still useful in a pinch if you need to light a bigger area.
When changing mode, the brightness doesnt just jump to the next lower brightness, instead it has a subtle smooth transition effect to the next lower brightness which I do really like (like a quick smooth ramping).
From my perspective following are things that I find great about the flashlight:
- Metal body and it feels premium
- switch button feels also good and it doesnt wobble. The click gives also a nice feedback.
- TIR lens
- simple UI (no strobe, no SOS, no turbo, no beacon). I think a keychain flashlight dont need any fancy modes.
- battery indicator
- size is perfect and the battery capacity is also good
- extra keychain ring
- user guide text is big enough and illustrated operation inctruction does help
- smooth ramping transition when changing mode is a nice effect
Things that could be improved:
- I think a lock mode is necessary, especially for a flashlight which will be stored with things that can accidentaly turn it on. A mechanical switch / a slide cover for switch / 3x click to lock-unlock is probably good.
- UI is simple but I still prefer this low to high cycle, instead current cycle high → low.
- Dont put moon mode if it is not really moon mode. Instead, put low/mid/high mode should be better.
- If lock mode is available, try to change the UI like:
[OFF] hold button: moon (really low lumens)
[ON] hold button: cycle through mode (4 modes are good: moon, low, mid, high)
[OFF/ON] 1x click button: turn on/off
[OFF] n x click button: battery indicator
[OFF] n x click button: lock or uses a mechanical approach as mentioned above
Overall, I do like this flashlight and it will stay on my keychain until it breaks I guess 
I hope this helps a bit in case you are interested in the flashlight.