Sunlight is a furling headsail’s worst enemy since the sail lives on the headstay for the whole summer. Most cruising sailors protect their sails from the sun with sewn-on leech and foot covers made of acrylic or UV treated Dacron. However the combination of constant sun exposure and being dragged across the rigging during each tack, takes a toll on these covers and they wear out rather quickly. In addition, they add weight to the back end of the sails they’re on which can reduce their light air performance.
An alternative is the UK-Halsey genoa sock. The sock will not disturb the light air shape of your sail by making the leech sag under the weight of the sewn on furling cover. The sock is totally separate from the sail and is raised up over the rolled genoa at the end of the day.
The sock is a much more effective way of covering a rolled up genoa, but it does take a bit more work. This is the perfect solution for sailors who use the same genoa for racing as well as cruising.