A Brief History of the Marque
Manufactured: 1968-1975 
Based in Vignola (Modena) and run by Vittorio Pellegrini, the company built motorcycles for young riders and lightweight sportsbike enthusiasts. Models include the Paciugo, the Paciughino, the Mistralino Mistralino TM 80 and TM 50, and numerous 50cc roadsters including the rather attractive Squalo.
The 1971 S50 had a 4-speed Franco Morini engine, clipon handlebars, Ceriani forks, Borani alloy rims, Grimeca or Bernardi 4LS brake. A Monza tuning kit was available with a larger bore, higher compression, performance exhaust and Dell-Orto 20mm carburettor (standard was 14/12). There was also a water-cooled version available.
1972 model range: Dolly, Personal (2 types) Sport Squalo Turbo, Sport Special Turbo, Scrambler Turbo, Cross-Strada S. Turbo. There were three 50cc Zundapp engined models: a Zundapp 125cc Cross and two 125cc Morini-powered machines - the Cross and the Regolarita.
Notes: 1. 1979 is also given as the final date of manufacture, but 1975 is more likely correct.
Sources: MC Storico Conti, sales literature et al
Yes it is a mono shock frame, please see photos re numbers etc which I hope will help you identify the model and year. I have decided to restore the bike as everything is there, albeit a little rusty. It will be good for my grandson an couple of years time. Frame now cleaned up with one coat of Hamerite more coats to follow. The front & rear tyres are 2.75/300 x 12 on plastic/nylon wheels.