In stock these darlington power transistor modules are made by Fuji Electric of Japan. As a part owner of Fanuc Ltd, Fuji have manufactured millions of components on behalve of Fanuc for various electronic devices.
In this instance the A50L-0001-0209 is also known as 6DI150A-060 in a special FANUC only package design. These transistors were fitted in yellow framed Fanuc AC Spindle Servo Units; from 6059 thru 6063 series drives.
This transistor is a six gate 150Amp per gate at 600 volt. These are always in stock and are genuine Fuji power transistor modules.