Vitreous pipe: Sealing plates (PACK OF 5)Sealing plate TRADE PACK for stove fitters Nine inch square plate with internal membrane of fireproof material. Is cosmetic and not designed to make any kind of airtight seal (smoke is contained in liner so is purely an aesthetic device). Brilliant product that provides a neat method of surrounding the black vitreous flue pipe as it passes through a closure register plate (the plate that seals off your chimney above your stove). Note: the sealing