This is one of the semiconductor types.
This part name is 30J124, GT30J124.
The package is TO-220SIS.
This product has Discrete 600V, 200A, IGBT functions.
Manufacturers of product is Toshiba.
Some of the text files within the PDF file :
Prior to the development of IGBTs, power MOSFETs
Datasheet 30J124 PDF Download :
[ 30J124-IGBT.PDF ]
Other data sheets within the file : GT30J124