This trial pack contains a fret of 8 AC4/3 delayed action autocouplings and MP4 mounting plates for use on 4mm scale layouts. They have also been successfully used in 0-16.5.
Also included are lengths of BW brass wire, NSW4 nickel silver wire, SIW4 soft iron wire, and a 4MAG permanent magnet. The inclusion of the mounting plates enables the AC4/3 coupling to be used on curves below 2′ radius, compared with the normal recommended minimum of 2′. They also have the added advantage of making the couplings easier to fit.
The frets shown are etched in 0.015″ brass. Each coupling is 32mm long and 10½mm wide; the mounting plates are 22mm wide x 8mm deep. The magnet is 25mm long, 7½mm wide and 4mm deep.