At wire leaders we differentiate between materials made of seven (1x7) or 49 (7x7) strands. The latter one is considerable smoother, softer and less susceptible to kinks. It also is more durable but also somewhat more expensive.
The seven stranded model seems to feature only disadvantages at first sight, since it is considerable stiffer and more susceptible to kinks. But the stiffness can also be an advantage, since the 1x7 wire leader is considerably less prone to tanglings with the trebles of the lure. Therefore lures, which tend to tangle with the leader, are better presented on a seven stranded material.
At most other fishing situations the 49-stranded material is the preferred choice, since it offers more flexibility and is pronouncedly more durable.
CORMORAN Wire Leaders