This fret contains 40 Mk3 delayed action autocouplings and mounting plates for use in 2mm scale. They have also been successfully used on 009 stock.
To fit and make the couplings fully operational, you will also require BW brass wire, SIW4 soft iron wire, and permanent (2MAG) or electromagnets (PK MAG). Alternatively, you could just purchase the S/ACN/3 starter pack, which contains the fret, the wires and six permanent magnets. A cheaper trial pack (T/ACN/3) is also available, with eight couplings and mounting plates, wires and one permanent magnet.
The actual size of the fret is 91½ x 99½mm; it is etched in 0.012″ brass. Each coupling is 16½mm long and 5½mm wide; the mounting plates are 4 x 12mm.