A fire damper for closing ventilation ducting in the event of fire has two or more sets, e.g. concentrically, of partial openings such as pilot holes, bores, centre-punch dimples or punch-outs to assist in connecting the fire damper to different types of supporting structure. The damper comprises a central flow opening and an outer flange 16 for mounting to the support structure; the outer flange having at least two sets of the partial openings 50, 52. Dampers installed in ducting where it passes through walls require fixing to the wall and fastener size spacing requirements vary depending on the wall type e.g. drywall (smaller fastener, closer to the opening) or masonry (larger fastener, further away). The where the pilots are holes they are of smaller diameter or partial depth or combinations thereof to avoid unused pilots compromising fire performance of the damper and to maintain visual appearance. The installer drills-out or punches-out to provide a fastener bore. The pilots may also be used to guide the pitch of ad-hoc mounting holes should on-site modification be required.
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