Yokiamy
(Yokiamy)
19
Fins are made to create more surface area which allow more heat transfer.
https://en.m.wikipedia.org/wiki/Fin\_(extended_surface)
It says not available at the moment, you can always ask them (i did, they were not available at that time as well)
I bought the driver from banggood
Or the finished jaxman
https://de.aliexpress.com/store/product/JAXMAN-E2L-3LED-TIR-LENS-flashlight-18650-flashlight-torch-CREE-XPG2-camping-cycling-outdoors/1812094_32812945810.html?spm=a2g0x.12010608.0.0.542b2437Gb8ZgQ