Generic name for 2-pin cable (DC)

Hi

I need a cable, that has a pairs of strain, used for DC (+/-). Like the second from here http://img.alibaba.com/img/pb/289/715/251/1275338866516_hz-cnmyalibaba-web1_42930.jpg Either direct a 2-pin cable, or a 4-pin cable which i could split in half.

The thing is, I need it with about 50m, and not only short one like 30cm or such.

What is the generic name for such a cable? I need to buy it from eBay (most other websites cost expensive shipping to switzerland).

Thanks a lot :)

Just a thought, the first set of wires look like trailor hook up wire the others could just be speaker wire which comes in a lot of diffrent gadges

Highgard