Encased switchgear box dedicated to BBC RT 2012 installations, for all types of hollow or solid partitions (aerated concrete, drywall, brick, plaster tiles etc...) The multi-diameter waterproof membranes have a double function: to seal the duct and to provide it with excellent resistance to tearing. The use of RT2012 multi-material boxes significantly reduces thermal loss and ensures better energy efficiency in the home. Multi-material housing double center spacing 71 mm Diameter 67 mm Depth 50 mm