Original post link: Reddit - Dive into anything
1, 01 and 02 seem to use the same head / driver. Mine are totally interchangeable with no impact on performance.
2, Get the SST20 4000k, forget about cool white. IRL I can’t tell any difference in lumens, even side by side. But the CT, tint, and especially CRI of 4kk is far far superior.
3, All four “heads” work with 1x 10440 no problem, yet. Don’t know how it’ll do in long term use. 2x 10440 will instantly damage the driver (That’s why it’s missing one head in the pic. It’s damaged and tossed).
4, WK01 w/ 1x 10440 at mid / high is marginally brighter than WK02 w/ 2x fresh AAA at high. However 10440 somehow removes the ugly green tint of SST20 4kk, which 2x AAA doesn’t.
5, W/ 10440, The low is still very very low. However I can’t tell much lumen difference between mid and high. I’d rather stick to mid.
6, Even if nothing goes wrong, I do not recommend using 10440. For one it lacks over-discharge protection. You wouldn’t know if your batt is still above 2.8v or not. However it does gradually go considerably dimmer as it approaches 2.8v.Also, IMO, 10440, or any rechargeable batteries, kinda defies the point of this light - carefree and accessible. (Unless you’re a physician, or work in professions that require low-output penlights, of course.)
7, I got mine for $5 each (incredible). But even at $9, it’s extremely hard to beat. They’re great night stand lights. I also plan use them when I need sth better than phone light in a pinch, yet don’t wanna spook / blind my “muggle” friends w/ my 8000 lm EDC.
8, While they’re very very slim and lightweight, they might not be very good keychain / EDC light (if you only EDC one light, that is), depending on how you use your lights. That being said, I find their current extremely affordable price really worth the quality, function, CRI, and nostalgia when you buy and put AAA batteries in a flashlight.
9, WK01 come with black clips, while 02 came with silver ones. If you care.