This part is a kind of semiconductor called 6N40C.
Function of this product has FQP6N40C.
Manufacturers : Fairchild Semiconductor
Image and pinout :

Some of the text within the PDF file :
FQP6N40C N-Channel QFET® MOSFET December 2013 FQP6N40C N-Channel QFET® MOSFET 400 V, 6.0 A, 1.0 Ω Description Features • 6.0 A, 400 V, RDS(on) = 1.0 Ω (Max.) @ VGS = 10 V, ID = 3 A • Low Gate Charge (Typ. 16 nC) • Low Crss (Typ. 15 pF) • 100% Avalanche Tested This N-Channel enhancement mode power MOSFET is produced using Fairchild Semiconductor’s proprietary planar stripe and DMOS technology. This advanced MOSFET technology has been especially tailored to reduce on-state resistance, and to provide superior switching performance and high avalanche energy strength. These devices are suitable for switched mode power supplies, active power factor correction (PFC), and electronic lamp ballasts. D GD S G TO-220 S Absolute Maximum Ratings Symbol VDSS ID IDM VGSS EAS IA [ ... ]
6N40C PDF Datasheet Download
