The Protected Elements Manager provides a way of making certain elements in your model immune to skeletonization. Use this feature to mark important elements in your model as not skeletonizable. Note that only pipes and junctions may be protected from skeletonization since all other node elements (valves, pumps, tanks, reservoirs, and all HAMMER CONNECT elements) are already immune to skeletonization. (TCVs are the noted exception to this rule and may be treated as junctions, if selected, during Series Pipe Merging.)