When using a shock leader, the leader is always connected to the mainline with a shock leader knot. This knot can cause resistance during casting or when using a boat to set the bait. The mainline can snag behind the knot and this often results in damage to the mainline during a cast. Pole Position has developed the Knot Protector Sleeve to overcome these potential problems. This subtle sleeve can be easily put on your mainline and slid over the shock leader knot