Prevents inside corner cracking when installed against a ceiling or concrete deck that may be subject to movement with backing material filling the head of wall gap. A co-extruded flexible gasket compresses and expands during deflection. Provides protection for up to 1/2" of deflection. Tear off strip leaves a clean finished edge. Can be used in fire-rated and non fire-rated assemblies.
https://www.trim-tex.com/products/overview/commercial-beads/deflection-beads/flat-deflection-bead