Lazy jacks are designed to contain and restrain a main sail when furling and reefing. The Harken Lazy Jack Kit uses a set of lines on either side of the main that attach high up on the mast and run down to the boom. The lazy jack lines then can capture and cradle the mainsail as it drops without falling on the deck. Lazy Jacks will not flake the sail but will hold the sail on the boom. Harken Lazy Jack Kit Installation Video by Sailrite gives step by step instruction on how to install a Harken Lazy Jack System. Harken Lazy Jack hardware attaches to the mast and boom with stainless steel pop rivets or stainless steel screws (included in Harken Lazy Jack Kits). The installation process is relatively easy and inexpensive compared to a Dutchman system because it does not require modifications to the sail (although full battens work better than standard battens).