Those are bi-wire/bi-amp speaker terminals. If you plan to use regular single-wire speaker cables, you will need something to connect the hi/low red(+) terminals together and and connect the hi/low black(-) terminals together. If you don't have the jumper plates that likely originally shipped with the speaker, you can use a short section of speaker wire to connect them together.
If you are going to use bare wire ends, instead of spades or banana plugs on the ends of your speaker cables, you can simply strip a longer section of the speaker insulation off, and run the end of the wire through the top red terminal and proceed down through the bottom red terminal. Tighten the terminals on both down onto the cable. Do the same for the black two terminals.
If you are going to use bare wire ends, instead of spades or banana plugs on the ends of your speaker cables, you can simply strip a longer section of the speaker insulation off, and run the end of the wire through the top red terminal and proceed down through the bottom red terminal. Tighten the terminals on both down onto the cable. Do the same for the black two terminals.