They will also fit many other Bowers & Wilkins Loudspeakers. Search: "changing tweeter coils on bowers wilkins speakers". Tweeter Ferro Fluid Information. Then 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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