1.05m Lengths. 10 x 4mm. Self-adhesive, single Fire Door Seal. Intumescent fire seals expand in the event of a fire and seal off the gap between the door and the frame, preventing the spread of fire and smoke. For maximum effectiveness, they need to be rebated into either the door frame or the door itself. It is very important to fit the correct size seal, please always check fire door manufacturers instructions. As a guide, only use 15mm seals on new door application and 10mm seals for replacement / retrofitting.