 Yes. So some of the monitor strings don't stretch anymore. They're made out of a material, 552X stuff that doesn't really stretch, but they also wear out. So the serving is the, so you got the main bow string, the main string that makes the bow string and then serving wraps around that, that protects the bow string in areas where it like takes a turn over the metal cams, where it hits a string stop. That's all called serving. That stuff will start to wear out.