Model Radio Workshop Clyde Puffer Whistle MRW66The MRW60 61 62 63 63 64 65 66 is a range of sound store units that are supplied with 7 basic sounds for model boats MRW60 BIG HORN 3 BLAST, MRW61 BIG HORN 2 BLAST, MRW62 MEDIUM HORN 1 BLAST,MRW63 STEAM WHISTLE 1 TOOT, MRW64 STEAM WHISTLE 7 TOOTS, MRW65 WHOOP WHOOP, MRW66 CLYDE PUFFER. They can also be supplied with a recording that you have made with a maximum length of 16 second, just send the MP3 file of your recording to Modelradioworkshop.