Suitable for use with all types of approved gas central heating boilers and appliances including standard radiant gas fires with flue outlets up to 125mm diameter.
They may also be used with some inset live fuel effect gas fires, classified by appliance manufacturer as suitable for use with Class 2 flue blocks.
Please note this product is not suitable for use with decorative fuel effect gas fires and inset live fuel effect gas fires requiring a minimum 175mm diameter Class 1 flue or solid fuel open fires and appliances.