Minimax Sprinkler Expansion Plates enable a clean, professional installation in earthquake-prone areas. They provide a one inch annular space (i.e. a larger hole) around the sprinkler to allow it to move in the event of an earthquake.
Expansion plates have a 5" (127 mm) or 5-5/16" (135 mm) outside diameter, and are available in either polished chrome or white. Custom finishes are also available upon request.