Bros, wonder how relevant is the following info?
Dondonghai is a flashlight seller, and has a SFN60 option. It lists Changda 昌达 as the manufacturer, supposedly changda is located in Fujian province.
https://item.taobao.com/item.htm?spm=a1z0d.6639537.1997196601.95.15a77484MPpzAP&id=628993143844
Changda. Are they the real original equipment manufacturer or just some middle man, not sure. But there is a fair bit of info in here
https://item.taobao.com/item.htm?spm=a21wu.12321156.go-detail.1.40a1f9a1ZdFTLl&id=658331735786
For eg, SFN55 used in the JKK76 and SFN60 in the dongdonghai flashlights
