The Korda Square Pear Leads have been designed exclusively from what Korda saw happening in Underwater Part 4.

Even as a swivel lead the fish will still feel more of the weight sooner because it's so short and one end of the lead is almost the same as the other. Only the movement of the swivel will affect a difference.

So in short, you have the most condensed swivel lead there can be, with flat sides that work in a fishing situation. This lead will cast almost as far as a normal pear lead but will have better hooking potential. To maximise distance use a swivel lead, as it will always cast further than an inline.