Need a pair ? Buy 2.
One non-perforated TANNOY 12" foam surround for 3128, 3108, 31xx, K Series, correct Kurt Muller part SR 278/8, GENUINE foams & factory fresh, with correct genuine glue & instructions, note plenty of fresh Tannoy issue glue provided, 30ml bottle, (watch out for the fakes about from China, the fakes will ruin your speakers sound).
Fits many Tannoy speakers, including Balmoral, Bradley, Chertsey, Cheviot MkII, also 3108 Windsor/ Buckingham 12" bass.