Circuit Protection, Electrostatic discharge protection, what is ESD protection,

 USBLC6 Series 2 Line 6 V Uni / Bi-Directional ESD Protection - SOT-23-6

https://www.futureelectronics.com/p/electromechanical--circuit-protection--esd-protection/usblc6-2sc6-stmicroelectronics-7124393