Metacaulk® Pipe Collars are prefabricated for through-penetration firestop systems using PVC, CPVC, ABS, PVC foam core, ABS foam core, FRPP, PEX pipe and electrical cable. Designed to reduce installation time by 25% and the simple locking mechanism insures easy installation. Metacaulk® Pipe Collars are economical because no backfill is usually required. UL Classified for both open and closed pipe systems. Complies to Required Environmental Exposure Testing of Accelerated Aging and High Humidity as per UL 1479 Fire Test of Through-Penetration Firestops. U.S. Patent No. 6,207,085.