This part is a kind of semiconductor called 2SB558.

Function of this product has Silicon PNP Power Transistors.

Manufacturers : SavantIC

Image and pinout :

Some of the text within the PDF file :

SavantIC Semiconductor Product Specification Silicon PNP Power Transistors 2SB558 DESCRIPTION ·With TO-3 package ·High power dissipation APPLICATIONS ·For power switching and general purpose applications PINNING(see Fig.2) PIN 1 2 3 Base Emitter Collector Fig.1 simplified outline (TO-3) and symbol DESCRIPTION Absolute maximum ratings(Ta= ) SYMBOL VCBO VCEO VEBO IC PC Tj Tstg PARAMETER Collector-base voltage Collector-emitter voltage Emitter-base voltage Collector current Collector power dissipation Junction temperature Storage temperature TC=25 Open emitter Open base Open collector CONDITIONS VALUE -100 -100 -6 -7 60 150 -65~150 UNIT V V V A W SavantIC Semiconductor Product Specification Silicon PNP Power Transistors CHARACTERISTICS Tj=25 unless otherwise spe [ ... ]

2SB558 PDF Datasheet Download