904 Grade Flue Liner is warranted for 20 years (conditions apply). Suitable to burn: wood, logs, peat, turf, house coal, coke, smokeless fuel, gas and oil. Application: A double skinned flexible flue liner suitable for relining within a masonry chimney. Flue liner is suitable for use with burning gas, oil, coal, coke, cured dry logs, cured dry peat, smokeless fuels. Construction: The flue liner has a smooth inner liner made from 904L grade stainless steel and is 0.12mm thick. The flue liner has a convoluted outer skin made from 904L stainless steel and is 0.12mm thick. Approval: Flue Liner is approved and listed by HETAS Pre - Installation: · Make sure the liner will go down the chimney (this can be done by pulling down a small section of the diameter liner you will be using) · Sweep your chimney. · Check you pot is in good condition, if you are NOT using a suspended cowl then remove the pot from the stack. Installation: · Flue Liner should always be fitted from the top. · Make sure the arrows are pointing upwards (gas flow). Maintenance: · It is recommended that chimneys serving solid fuel appliances be swept and maintained as frequently as necessary but at least once a year.