Headsails on furlers are often protected by UV strips (otherwise known as sacrificial strips, leech strips etc). This cover doesn’t often get checked until it is very noticeably damaged, which can lead to the damage of the sail it is supposed to protect.
To prevent this check the UV strip for the following:
– holes of any kind (holes caused by rubbing or catching may need extra help in preventing a re-occurrence)
– missing stitching, stitching often gets destroyed by the sun before the strips needs replacement
– severe discolouration of the cloth can be a sign of it approaching the end of its life
– you can tear it easily with your fingers
– discolouration of the sailcloth it is protecting
It is often easier and cheaper to repair/replace the UV strip than it is to replace the entire sail.