Leaders for King Fishing

Why not single? Single is used just as much as seven, it is personal preference.
It apparently doesn't really matter, single or seven, half a dozen one way, six the next.

I like #30 sevenstrand wire about 2' long, a thick circle hook 4 to 6 Ot and a treble stinger on about 6" long. That Stinger gets em.

Single strand works fine too. I personally think that 7 strand is somewhat better.

Here are four reasons I suggest 7 over single:
1. Since it's more flexible, bait swims more naturally.
2. Single strand is more prone to having a kink set in it. If the kink is severe enough, it's more likely to fail.
3. Making leaders with 7 is much easier to do correctly. Unless you're proficient at making a haywire twists it's easy to do wrong.
4. It is at least twice as quick to tie a 7 strand leader.