• Basic encasement for recessed installation, made of ABS plastic. • Spigot made of ABS plastic, integrating the backdraught shutter compliant with DIN 18017-3, as certified by TUV German Institute. • Spigot nominal diameter: 80 mm. • Square frame to prevent entry of dirt and plaster. • Connection port to connect a spigot (QE-AD cod. 21118, available as accessory) able to extract air from a second room. • Possibility of drywall installation.