Any standard speaker wire that will fit. Wire is measured in gauge, represented with a number. The lower the number, the larger the wire. Probably the largest wire it can take is 16ga. So, 16ga OFC (oxygen free cable) speaker wire. You can get it at pretty much any home supply store, or THIS from Monoprice (just be certain to select 16 or 18 ga, not 12 or 14) or THIS from Amazon. Those are both USA links. I don't know where you are located.
I'm looking for the wires that connect into the black and red port both on the amplifier and speaker/sub. Can you check the attached images and let me know the cable type/name? Is it the same as the amazon link you shared?
That's the wire. It won't be black and red, but all that matters is getting the positive (red) connected to positive on both ends of every wire. The wire has a marker, like a red line, to indicate which side is which. Typically people connect the marked side to positive. Then connect the other to negative, which is black on the speakers, but might not be on the receiver. You measure how long you need the wire to be, cut it and strip off about 1/2" of insulation from both ends and then twist the wires so they're less likely to get caught in the spring clips on the speakers. You can (carefully) use a knife for that, but there are tools specifically designed for it as well. Be sure to get enough wire, because there are a lot of wires to connect. Most of them, if not all of them, go to the bass module first, then on to the speakers. 50 feet seems like a lot, but it gets used up fast.
HERE'S a basic video showing how it works. The difference with the Bose system is connections go to the bass module, then on to the speakers, so there are twice as many wires and connections.
HERE'S a basic video showing how it works. The difference with the Bose system is connections go to the bass module, then on to the speakers, so there are twice as many wires and connections.