2 Bowers & Wilkins DM604 S3 Generic Replacement Tweeter Loudspeakers Coils Foils

If they are slightly wider, then all you need to do is to put a very thin edge of superglue around the edge of your plastic tweeter surround (use the tip of a cotton bud) & then place the tweeter coil - foil in place using the magnet part of your complete unit to line it up while the glue sets.

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