The Chimney Plug is a mix of reinforced concrete and heat resistant chemicals. The plug weights around 6kg and sits on top of heat shield gasket that is placed on top of the flue pot. The Chimney Plug fits flue pots from 7-12 inch. The plug is only for unused chimneys The Chimney Plug Minimises Heat Loss from disused Chimney Flues Our revolutionary Chimney Plug minimises heat loss from disused chimney flues.Help to increase your BER rating value by putting a plug on your heating cost and save up to 30% on annual heating bills. Gives maximum output with electric fire installation. Other points include Increase BER rating 100% Heat Resistant Reduces Draft Reduces Noise Levels Stops Rain, Snow & Sleet Rust & Corrosive Free No moving Parts Naturally Blends In Prevents Residual Fumes Easy to install and remove Please contact our team at Dermot Kehoe's Homevalue for pricing & availability.Available for local home/nationwide delivery.