This is one of the LED driver types.
See the preview image and the PDF file for more information.
Part number : YX8018
Functions : Solar LED driver
Package information : TO-94 ( 4 Pin ) Type
Manufacturer : Shiningic
YX8018 learn more : The two 1.25V charge current or one Lights in a stable manner LED in the pond. Light of the sun Saw And to charge the rechargeable battery