The IRFZ44E is a 60 V, 48 A N-Channel HEXFET power MOSFET in a through-hole TO-220AB package, part of Infineon's established HEXFET series.
Date-code and authenticity verification is standard practice for obsolete lots.
Package and mounting — TO-220AB
The through-hole TO-220AB package with three leads mates into a standard 0.100-inch pitch footprint. The metal tab is the drain connection; thermal pad area under the tab sets the junction-to-case thermal resistance. For high-current layouts, the source lead should be kept short to minimise parasitic inductance in the gate-drive loop.