From Klober
The Bonding Strip is an excellent way of providing a watertight junction above the party wall between different roof finishes when re-roofing. Key Features Provides a weathertight junction between differing roof finishes. Lightweight and flexible to handle for quick and easy installation. Safe and easy to cut. UV resistant Safe and easy to cut BBA certified Fire tested to comply with BS476: Part 3 SAB andPart 7 Class 3.