This part is a kind of semiconductor called 10N50K-MT.

Function of this product has N-CHANNEL POWER MOSFET.

Manufacturers : Unisonic Technologies

Image and pinout :

Some of the text within the PDF file :

UNISONIC TECHNOLOGIES CO., LTD 10N50K-MT Preliminary 10A, 500V N-CHANNEL POWER MOSFET  DESCRIPTION The UTC 10N50K-MT is an N-channel mode power MOSFET using UTC’s advanced technology to provide customers with planar stripe and DMOS technology. This technology allows a minimum on-state resistance and superior switching performance. It also can withstand high energy pulse in the avalanche and commutation mode. The UTC 10N50K-MT is generally applied in high efficiency switch mode power supplies, active power factor correction and electronic lamp ballasts based on half bridge topology.  FEATURES * RDS(ON) < 0.68 Ω @ VGS = 10V, ID = 5 A * High Switching Speed * 100% Avalanche Tested  SYMBOL 2.Drain Power MOSFET 1.Gate 3.Source  ORDERING INFORMATION Ordering Number Lead [ ... ]

10N50K-MT PDF Datasheet Download