I'm pretty sure that the TheMightyHobie18 I used to have had a wire luff halyard for the jib too. Sister clips are two little clips - usually flat pieces of stainless - that have a tiny slot on the side that opens into the round interior. You put two clips at 90 degrees to each other and they will slide inside each other. They have no moving parts and stay connected when they can be protected like in the jib luff. Makes it easy to remove the halyard tail used to hoist the sail.