This part is a kind of semiconductor called FQPF20N60.
Function of this product has 20A N-Channel MOSFET.
Manufacturers : Oucan Semi
Image and pinout :

Some of the text within the PDF file :
FQP20N60/FQPF20N60 600V,20A N-Channel MOSFET General Description Product Summary The FQP20N60 & FQPF20N60 have been fabricated using an advanced high voltage MOSFET process that is designed to deliver high levels of performance and robustness in popular AC-DC applications.By providing low RDS(on), Ciss and Crss along with guaranteed avalanche capability these parts can be adopted quickly into new and existing offline power supply designs. VDS ID (at VGS=10V) RDS(ON) (at VGS=10V) 100% UIS Tested 100% Rg Tested 700V@150℃ 20A < 0.37Ω TO-220 Top View TO-220F D G S Absolute Maximum Ratings TA=25°C unless otherwise noted Parameter Symbol AFQOPT20N60 FQPF20N60 Drain-Source Voltage VDS 600 Gate-Source Voltage VGS ±30 Continuous Drain TC=25°C Current TC=100°C Pulsed [ ... ]