This part is a kind of semiconductor called JRC-21F.

Function of this product has PCB Relay.

Manufacturers : YUEQING HENGWEI ELECTRONICS

Image and pinout :

Some of the text within the PDF file :

www.chinahwe.net YUEQING HENGWEI ELECTRONICS CO.,LTD. PCB Relay —JRC-21F(4100) JRC-21F(4100) 1C DC12V Order Model Coil Voltage:3,5,6,9,12,24VDC Contanct Form:1A 1C Relay Type Contact Material Contact Resistance Rated Load Coil Voltage Coil Power Contact Data 1A,1C AgCdO ≤100MΩ(1A 6VDC) 3A 3A 125VAC/30VDC Coil Specificaton 3~24VDC 0.2W,0.36W Technical Specification ≥100MΩ(500VDC) ≥1000VAC ≤10ms ≤5ms 1×10 7 1×10 5 PCB 4g Dimension / Mounting holes / Wiring dragram [ ... ]

JRC-21F PDF Datasheet Download