The 2SD882, 2SD-882, 882 is a NPN transistor manufactured by using planar technology resulting in rugged high performance devices. The complementary PNP type is 2SB772.
The 2SK3451, 2SK-3451, K3451, 3451 is a Transistor MOSFET N-Channel Silicon 600V 13A 80W 3-Pins (3+tab) TO-220F In The FET Transistors, MOSFETs Category. Check Part Details, Parametric And Specifications.
The DC-DC module based on LM2596 advocate current to 3.0A, but only to 1.8A.However, being introduced module adds a heatsink, using high-power devices. This module can easily reach 4A, 50W.