This part is a kind of semiconductor called SL24.

Function of this product has TVSarray Series.

Manufacturers : Microsemi Corporation

Image and pinout :

Some of the text within the PDF file :

SL03 8700 E. Thomas Road Scottsdale, AZ 85251 Tel: (480) 941-6300 Fax: (480) 947-1503 thru SL24 TVSarray™ Series DESCRIPTION (300 watt) This 3 pin ULTRA LOW CAPACITANCE TRANSIENT VOLTAGE SUPPRESSOR is designed for use in applications where protection is required at the board level from voltage transients caused by electrostatic discharge (ESD) as defined by IEC 1000-4-2, electrical fast transients (EFT) per IEC 1000-4-4. This product provides unidirectional protection for 1 line by connecting the Input/Output line to pin 1, pin 2 to common or ground and pin 3 (is not connected). The SL03 thru SL24 product provides board level protection from static electricity and other induced-voltage surges that can damage sensitive circuitry. These TRANSIENT VOLTAGE SUPPRESSOR (TVS) Diode Arrays p [ ... ]

SL24 PDF Datasheet Download