Separate cap fits up to a 2" pipe. Features spring tension attachment, which eliminates the need to replace the entire vent just because of a lost cap top. Replaces lost or damaged RV Plumbing Vent Caps Cap fits up to a 2" pumbing vent pipe Made with UV inhibitors to extend the life of your vent cap Features spring tension attachment, which eliminates the need to replace the entire vent Vent cap only (base not included)