Microplus were a range of GRP boats (glass reinforced plastic - or fibreglass) produced in the UK in the 1960s and 1970s.
[1] In the mid-1970s the company split into two manufacturing groups, Microplas and Chrisidon Marine Limited.
Microplas continued to produce body shells and later plastic pipes, while Chrisidon Marine manufactured the boats, by now renamed Microplus.
Generally the model name has a direct correlation with the overall length of the completed moulding.
[3] An enthusiast and owner has created a website and forum dedicated to the history, maintenance and running of the Microplus marque at: [1]