Midtherm HTS Twin Wall Flue - Ventilated Firestop & CollarThe Midtherm HTS Ventilated Support Plate is a collar attached to the plate houses and supports strips of material that expand when the activation temperature is exceeded, reducing gaps to restrict flame ingress. Complete with a decorative cover and and available in a stainles steel or in a powder coated white finish that matches most ceilings. Only suitable for use when penetrating the ceiling in the same room as the appliance. Made od stainless