This part is a kind of semiconductor called LM2406.
Function of this product has Monolithic Triple 9 ns CRT Driver.
Manufacturers : National Semiconductor
Image and pinout :

Some of the text within the PDF file :
LM2406 Monolithic 9 ns Triple CRT Driver June 1995 LM2406 Monolithic Triple 9 ns CRT Driver General Description The LM2406 is an integrated high voltage CRT driver circuit designed for use in color monitor applications The IC contains three high input impedance wide band amplifiers which directly drive the RGB cathodes of a CRT The gain of each channel is internally set at b14 5 and can drive CRT capacitive loads as well as resistive loads presented by other applications limited only by the package’s power dissipation The IC is packaged in an industry standard 11 lead TO-220 molded plastic power package See thermal considerations on page 4 Features Y Y Y Y Y Output swing capability 50 VPP for VCC e 80 40 VPP for VCC e 70 30 VPP for VCC e 60 Pinout designed for easy PCB layout 1V to [ ... ]
LM2406 PDF Datasheet Download
