30 V, 15 A per diode — what the ratings mean
The maximum reverse voltage (Vr) is 30 V, so it is intended for low-voltage, high-current rails — typical in switch-mode power supply outputs, OR-ing diodes, and freewheeling diodes in 12 V or 24 V systems. The forward voltage drop is 490 mV at 15 A per diode, which keeps conduction losses manageable for the current level.
The TO-220 package allows direct heatsink mounting through the metal tab, which is electrically common with the cathode. The through-hole leads suit point-to-point wiring or PCB mounting with adequate copper area for heat spreading.