I use a soft PVC stitched on to the sail, they are sewn over the batten pockets and extend past the end of the battens. This covers the batten ties and the knots and battens dont get caught on the jib halyard. They work fine in all but the very lightest of air. They also protect the sails. (you know how they wear thru at the pockets). It is also a good idea to sew the pvc on the two batten pockets on the main sheet where they rub on the sidestays. It will last heaps longer.