We can make a pair of Kitesurfing lines to what ever length you want, we generally use heavy duty North lines, and we re sleeve, so if you measure the lines you already have and tell us how long they are loop to loop. We can make a pair of lines up to 25m. These as I say are heavy duty pre-streched 660Ib north lines. Alot of lines sets these days have shorter middle lines and longer outer lines.