http://www.sailrite.com/Installing-Lazy-Jack-Slits-in-a-Sail-Cover-Video A sail cover that utilizes lazy jack lines will sometimes require additional slits in the cover to allow for passage of the lazy jacks lines. The Installing Lazy Jack Slits in a Sail Cover Video provides step-by-step instructions on how to install and reinforce slits in a way that will protect where the lines pass through the sail cover.